 Friday 7
A couple days ago I posted an update on the Watkins-Johnson
databook page that had an unauthorized gag graph titled, "WJ-G1/SMG1 Phase vs. VCTL vs.
Frequency vs. Phase of the Moon." When RF Cafe visitor and sometimes contributor Dr. Marek
Klemes* read that, he sent me a note about remembering this
"Delayed Light Turn-Off"
circuit from the Signetics 555/556 Timer Databook. It took a bit of creative Googling,
but he managed to find the datasheet (to the right). The text was a bit washed out from
the original low resolution scan, so I reproduced the labels (green). This Rube Goldberg-ish
contraption works thusly: After a delay determined by the values selected for R1
and C1, the output of the NE555 timer goes high and causes resistor RL
to heat up enough to ignite match M1. M1 subsequently lights the
fuse on firecracker FC1, which has tied to its body a string that wraps around
a pulley and holds a rock (which weighs precisely 2π pounds ...
PierCon Solutions
is a solid, tenured, and proven wireless consulting and engineering firm based in Lincoln
Park, NJ. PierCon is a recognized leader in the wireless designs of in-building coverage,
broadband, WiMAX/LTE, microwave, cellular, public safety, PCS, iDEN, and WiFi. As a provider
of world-class engineering and consulting services our team of dedicated RF Engineers
is seeking additional talent to help us continue our path to success. This
RF Field
Engineer position acts as the Site Engineer and Site Inspector for a large scale
Public Safety communications Project located in Harriman, NY. The Field Engineer will
perform daily surveillance and inspections of contractors / sub-contractors in accordance
with contract specifications ...
Kenneth Puglia has a good article in Microwaves & RF
magazine titled, "A Brief Tutorial on Microstrip Antennas - Part 1" (here is
Part 2). Says Mr. Puglia, "This article, the first of a multi-part
series on microstrip antennas, discusses antenna characterization - from antenna parameters
to key attributes. A significant performance element in communication and radar systems
- as well as wireless devices - is the antenna. It may be defined as a transducer between
a guided electromagnetic (EM) wave propagating along a transmission line, and an EM wave
propagating in an unbounded medium (usually free space) or vice versa. The antenna is
required to transmit or receive EM energy with directional and polarization properties
suitable for the intended application. This multi-part tutorial explores the radiation ..."
With today being the 77th anniversary of America's
entry into World War II with the Japanese bombing of Pearl Harbor, I thought this
advertisement from a 1942 issue of the ARRL's QST magazine would be of interest.
Most of us have heard about the neighborhood collections for tires, glass, newspaper,
cans, and cloth in order to help support the war effort. Probably not many have also
heard about the
Signal Corps' call for milliammeters! That's right, the huge, rapid build-up of electrical
and electronic equipment for radios, vehicles, and factory equipment. Many meters were
needed for monitoring status and making process adjustments. America had an ample supply
of meters in the hands of Amateur radio operators; all that was required was to separate
the Hams from their meters. Fortunately, an appeal to patriotism was sufficient motivation
back then ...
Withwave has introduced
Board Edge 2.92 mm (SMA) connectors are specially designed for high frequency (DC-40 GHz)
substrates to minimize electromagnetic transition effects from coaxial to Microstrip/CPW
structure. We solve your performance and cost problems with various types of board edge
connectors according to substrate clearance. Board clearances of 0.6 mm to 3.6 mm
available ...
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!
"NTT DOCOMO and Rohde & Schwarz have joined
forces to set up the first
ultra-wideband channel sounder for mobile communications exceeding
100 GHz. They conducted radio wave propagation experiments at frequencies up to 150 GHz.
The frequency bands from 100 GHz to 300 GHz are expected to enable high-speed and large-capacity
communication for the next generation beyond 5G. In the experiments, DOCOMO and Rohde &
Schwarz measured and analyzed the effects of radio wave propagation characteristics and
shielding effects in the mm-Wave range. As a result, the two companies pioneered new
frequency bands and contributed to the realization of terabit-class mobile ..."
Thursday 6
As with so many aspects of electronics, physics,
economics, medicine (well, maybe not medicine), the basics do not change a whole lot
since first being discovered. If you are a newcomer to the world of electronics and are
trying to come up to speed on
transistor fabrication and operation, even this article that appeared in a 1958 issue
or Radio-Electronics magazine will be useful to you. Figure 1 reminds me
of a situation I witnessed while working as a technician at Westinghouse Oceanic Division,
in Annapolis, Maryland. If you've heard this before, please indulge me. One of the managers
there, who was not a degreed engineer (although he held the title), one day while in
the lab actually soldered a pair of 1N4148 diodes together back-to-back per Figure 1
and tried biasing it to function like a transistor. A "real" engineer, whom I greatly
admired, stood watching with his mouth agape as he watched. Before he could politely
explain why the diode pair is not the same as the intimate PN junctions of an actual
transistor ...
Anatech Electronics, Inc. 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. Anatech has introduced three
new filter designs: a surface mount 2050 / 2250 MHz Ceramic Duplexer, a surface mount
62.5 MHz IF SAW Filter, and a 537-563 MHz / 2432-2480 MHz Duplexer with N-type connectors.
Custom RF filters designs are used when a standard cannot be found, or the requirements
are such that a custom approach is necessary ...
Even with the domination of LED, plasma, and LCD
displays, there are still a whole lot of cathode ray tubes (CRTs) on the job. Hobbyists
workbenches are filled with them for sure, but design and manufacturing facilities still
have huge inventories of test equipment with CRTs, and a lot of computer equipment on
the production line with CRTs sitting in racks. LED, LCD, and plasma displays all have
their own claims to genius on the part of their designers, but cathode ray tube designers
- and the designers of the driver circuits - deserve special recognition. Consider the
physics and materials involved: glass, phosphor, magnetics, thermonics, electrostatics
and electrodynamics, relativity (electrons traveling at relativistic speeds gain mass,
requiring stronger deflection fields) ...
Transient Specialists, a leader in EMC rentals
for over 30 years, announces that they will be offering rentals, sales and a set-by-step
guide of the
IEC 61000-4-2 setup including all components and cords. This complete
ESD immunity setup includes vertical coupling plane (VCP), horizontal coupling plane
(HCP), ground coupling plane (GCP), ESD table, and all required cords. EN/IEC 61000-4-2
puts forth specific requirements for all components of the setup for this electrostatic
discharge (ESD) standard. This setup can be rented or purchased as a whole, or individually
to enhance a preexisting test setup. The setup includes, an all wood table with removable
legs, vertical coupling plane (VCP), horizontal coupling plane (HCP) ...
That fully exposed cable harness seems like a
major Achilles Heel to an otherwise hardened battle-ready system. "Russian state media
published video earlier today of its latest laser weapons system, the
Peresvet. The move comes just a day after the U.S. said it would
likely pull out of a key arms treaty between the two countries, and the timing of the
video's release doesn't appear to be a coincidence. 'Peresvet laser systems, based on
new physical principles, entered combat service in [a] testing regime with the Russian
armed forces,' Russian Defense Ministry's newspaper said, according to an English translation.
When President Vladimir Putin made his annual address to Russia's Federal Assembly back
in March ..."
Rohde & Schwarz develops, produces and markets
test & measurement, information and communications technology.
Focus is on test and measurement, broadcast and media, cybersecurity, secure communications,
monitoring and network testing. Markets serviced are wireless, the automotive industry,
aerospace and defense, industrial electronics, research and education, broadcast and
media network operations, consumer electronics, cybersecurity for business and governments,
communications and security solutions for critical infrastructures and the armed forces,
reconnaissance equipment for homeland and external security, and much more ...
"BAE Systems has booked a $9.2M Defense Advanced
Research Projects Agency contract to develop new machine learning algorithms and other
related tools for users to better identify radio frequency signals. Phase one of the
Radio Frequency Machine Learning System program will see BAE focus
its creation work on using cognitive approaches to make the algorithms with feature learning
techniques. Scientists will also work to create algorithms that help users determine
signals that are important versus those that are not in real time through a deep learning
approach, BAE said Tuesday. DARPA envisions this program as further advancing technology
for autonomous vehicles and image and speech recognition ..."
Wednesday 5
The
Boeing B-52 Stratofortress long-range bomber has been in continuous service since
1954. Production of new aircraft ran from 1952 through 1962. Now 59 years hence at version
'H,' it is still our nation's primary long-range bomber. That is a great testimony to
the aircraft's initial design and construction, but a sad testimony to our ability to
design and build a complete replacement. The B-1 bomber was a dismal failure and the
B-2 Stealth bomber is too expensive to build and maintain in large quantities. This story
from a 1957 edition of Radio & Television News reports on the "K-System" computerized
bombsight gear installed in early B-52s that used radar for targeting. According to the
writer, nearly 1,000,000 American defense company workers at companies like Eastman Kodak,
General Motors, General Mills (yes, the breakfast cereal people), Motorola ...
Skyworks
Solutions has created a video titled, "Sky5
Makes 5G Work Video." It provides a simple explanation of how 5G will work and explores
how their Sky5™ platform resolves system complexities and enables this next generation
communication standard. As a premier provider of wireless front-end solutions, Skyworks
is an expert in connectivity. They are enabling the 5G evolution by advancing our technology
leadership and extending our product reach to power some of the world's most exciting
communication platforms. Skyworks is a member and key contributor to the industry's most
influential standards organizations including ETSI and 3GPP ..
When you were a kid, did your mother warn you
about sitting too close to the television because doing so would cause you to be near-sighted
or otherwise "ruin" your eyes? Mine did, and I'm now very near-sighted, but it is doubtful
that sitting too close to the TV is the reason. In fact, according to Linus Van Pelt's
comments to his sister, Lucy, in this 1962 Peanuts comic strip, ophthalmologists tried
to counter the misconception about too-close boob tube viewing. There is another strip
where Linus challenges Lucy's assertion that reading in dim lighting can hurt your eyes.
The real concern as it turns out, according to professional alarmists, was the massive
doses of
x-radiation pouring out of the front of the early color TV sets. To hear the distractors
tell it, you could almost see the skeleton of anyone sitting in close proximity to a
color TV screen. The high voltage (25-35 kV) on the cathode ray tube (CRT) produced
x-rays ...
KR Electronics designs and manufactures high quality
filters for both the commercial and military markets. KR Electronics manufactures all
filter types: lowpass, highpass,
bandpass, bandstop and individually synthesizes 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. Please visit their website today
to see how they might be of assistance ...
My
Vise-Grip pliers have performed a lot of hard duty over the decades.
Many rusted nuts and bolts would still be unremoved if it weren't for their sharp, corrugated
locking jaws. I have 10", 7", and 4" w/cutter, and 6" long nose models. These are all
manufactured under the Petersen Manufacturing Company name, before they bought Irwin,
who now manufactures Vise-Grips. Even high quality tools eventually show signs of wear
after decades of use and abuse. A few of mine had jaws worn down to the point where they
no longer would "bite" into the bolt head or nut being clamped. I was about to buy a
couple new pairs of Vise-Grips, but then wondered if I could recondition the jaws to
put the pointed shape back on the jaws with a triangle file. Being hardened steel, a
lot of times a standard file will barely scratch the surface, but in this case I managed
to dress the jaws of four pairs of Vise-Grips before the file (double taper triangle)
got dull ...
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 ...
"The proposed strategy relies on manipulating
with high precision an unimaginably huge number of variables.
Quantum computing is all the rage. It seems like hardly a day goes
by without some news outlet describing the extraordinary things this technology promises.
Most commentators forget, or just gloss over, the fact that people have been working
on quantum computing for decades - and without any practical results to show for it.
We've been told that quantum computers could 'provide breakthroughs in many disciplines,
including materials and drug discovery, the optimization of complex manmade systems,
and artificial intelligence.' We've been assured that quantum computers will “forever
alter our economic, industrial, academic ..."
Tuesday 4
Recognizing that many people were reluctant to
approach the theoretical aspect of electronics as it applied to circuit design and analysis,
QST magazine (the American Radio Relay League's monthly publication) included
equations and explanations in many of their project building articles. Occasionally,
an article would be published that dealt specifically with how to use
simple mathematics. In this case, the June 1944 edition, we have the second installation
of at least a four-part tutorial that covers resistance and reactance, amplifier biasing
(tubes since the Shockley-Bardeen-Brattain trio hadn't invented the transistor yet) oscillators,
feedback circuits, etc. In the July 1944 edition is the third installation of at
least a four-part tutorial that covers resistance and reactance, amplifier ...
The
Early Television
Foundation is dedicated to the preservation of the technology from the early days
of television. Our website's mission is to preserve and make available to the public
the history of early television, from the mechanical systems of the 1920s through the
introduction of color television in the 1950s.
Axiom Test Equipment allows
you to rent
or buy test
equipment, repair test
equipment, or sell or trade
test equipment. They are committed to providing superior customer service and high quality
electronic test equipment. Axiom offers customers several practical, efficient, and cost
effective solutions for their projects' TE needs and is committed to providing superior
customer service and high quality electronic test equipment. Please check out Axiom Test
Equipment today! ...
RF Cafe visitor and former Watkins-Johnson engineer
Paul Johnson (no relation to the "J" in WJ), recently sent me this note regarding the
Watkins-Johnson catalog page that contained the famous "Phase
vs. VCTL vs. Frequency vs. Phase of the Moon" graph on the WJ-G1/SMG1 Voltage-Controlled
Attenuator Module (5 to 2,000 MHz). We all suspected it was not an officially approved
feature, but now a first-hand account of the prank confirms it ...
Agile Magnetics is offering this "Design Considerations
for High Frequency Transformers" e-book as a free download. Taking a look at the
principles and calculations associated with custom high frequency transformers With the
need for more efficient and smaller power supplies providing power to electrical equipment,
high frequency transformers are a critical component of supplying power to modern electronics.
The book takes a look at the principles and calculations associated with these types
of custom transformers. This guide will discuss: Basic Principles, SMPS Topology, Off
Grid Energy Production, Designing ...
San Francisco Circuits' (SFC) new website provides
customers with the information and tools necessary to effectively work with SFC to build
Printed Circuit Boards (PCB) that meet demanding design requirements. The site enables
users to get a quote online by providing specifications and uploading designs to SFC
using a password protected customer area of the site. In addition, the website hosts
an educational PCB School, a password-protected learning environment where engineers,
designers, and others involved in the design and use of PCBs can learn about the intricacies
of their creation, integration, testing and more. A number of PCB guides and explainers
on key topics are also available ...
Rohde & Schwarz develops, produces and markets
test & measurement, information and communications technology.
Focus is on test and measurement, broadcast and media, cybersecurity, secure communications,
monitoring and network testing. Markets serviced are wireless, the automotive industry,
aerospace and defense, industrial electronics, research and education, broadcast and
media network operations, consumer electronics, cybersecurity for business and governments,
communications and security solutions for critical infrastructures and the armed forces,
reconnaissance equipment for homeland and external security, and much more ...
"Soldiers on the ground are now capable of rapidly
reacting to electronic and cyber data rather than waiting on their higher echelons. Soldiers
assigned to Headquarters and Headquarters Company, 1st Armored Brigade Combat Team, 1st
Cavalry Division, currently deployed in Poland, are among the first brigades supporting
Atlantic Resolve to train on a new system that enables a team to forward deploy and respond
to enemy frequencies using new electronic warfare, or EW, technology.
Electronic warfare, known as the battle in the electromagnetic spectrum,
relies on data and signals to survey, fight and defend. Collecting enemy radio signals,
sensing radar of an incoming threat, and utilizing radio waves ..."
Monday 3

Nuts & Volts magazine has an article by Clark Hamilton titled, "Mass Confusion: The End of the Kilogram as We Know It," that reports
on the newly adopted standard for mass that is based on a quantum mechanical property
rather than a physical metal bar (which, BTW, has inexplicably been losing mass over
time). "This November, in Versailles, France, representatives from 57 countries are expected
to make history. They will vote to dramatically transform the international system that
underpins global science and trade. ..."
The IEEE also has a news story titled, "Historic SI Unit Overhaul Redefines Kilogram, Ampere, More" on it.
"The International Bureau of Weights and Measures will redefine four base units in terms
of fundamental constants in nature. A governing body unanimously voted Friday for the
biggest ever overhaul of the international system of units (SI), which will redefine
four base units: the ampere, kelvin, kilogram, and mole. 'It's a moment of quite major
significance in our obsessive little world of metrology ..."
RF
Cascade Workbook 2018 is the next phase in the evolution of RF Cafe's long-running
series, RF Cascade Workbook. 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 ...
Thanks to PCB Directory for deciding to help
deliver RF Cafe to you, my visitors. 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 (e.g., material, flexible, rigid), Geographical
location, and more ...
Fairview Microwave has recently expanded their
line of
RF coaxial probes into the 40 GHz frequency range for use in high-speed communications,
microwave components and networking applications. Fairview Microwave's expanded line
of coaxial RF probes now includes four models that deliver 10 dB maximum return loss
over a broad frequency range of DC-40 GHz. These new RF probes are offered in GS and
GSG configurations with a pitch of 800 or 1500 microns and a 2.92mm interface; they are
gold-plated and feature compliant pogo pin contacts that allow for a wide range of probing
angles. These coaxial probes can be used by hand, with or without a probe positioner,
and can be cable mounted or mounted with Fairview's multi-axis probe positioner. These
coaxial RF probes are ideal for signal integrity ...
If the technology futurists of the 1970s had been
correct, by now we would be reading historical articles on the early days of holographic
television. I have read, though, that any day now a battery-powered flying car with a
holographic dashboard / instrument panel display is going on sale. Not. The Sadly, the
Ercoupe (pronounced "air coupe") is still the closest thing to "an airplane in every
garage." But, I digress. This story from a 1953 issue of Radio & Television News
magazine reports on the roll-out of the country's first color television system: The
field sequential system (aka the CBS system). It was a fine system, but unfortunately
the modulated signal format was not backward compatible with the existing B&W system.
That meant separate receivers for B&W and color televisions. Even as CBS TV sets
were being produced, the NTSC was working on a replacement system that permits co-existence
of B&W and color signals. Note the mention of how the DPA, in 1951 ...
Concentric Technology Solutions is your one stop
source for RF shield boxes,
RF enclosures, Bluetooth testers, WiMax testers, RFID testers and RF power amplifiers.
CTS can supply off-the-shelf or custom products for your testing needs requiring maximum
RF shielding in order to produce repeatable results in laboratory and production environments.
Manual and pneumatic operation is available. TEM cells, glove boxes, forensic enclosures,
and special purpose per your requirements.
"Reseachers
at ETH Zurich have developed a modulator with which data transmitted via millimeter waves
can be directly converted into light pulses for optical fibers. This could make covering
the 'last
mile' up to the internet socket at home considerably faster and cheaper. The high
oscillation frequencies of light waves make them ideally suited to fast data transmission.
They can be sent through optical fibers and easily carry hundreds of billions of bits
(gigabits) per second. The 'last mile' from a central fiber optic cable to the internet
socket at home, however, is the most difficult and expensive. Some alternatives, for
instance 4/5G mobile telephony, are cheaper, but they cannot provide all users simultaneously
with the extremely high transmission rates required by today's data-hungry applications
such as streaming TV ..."
Sunday 2
Each week, for the sake of all avid cruciverbalists
amongst us, I create a new technology-themed
crossword puzzle using only words from my custom-created lexicon related to engineering,
science, mathematics, chemistry, physics, astronomy, etc. 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, see someone or something in the exclusion list
who or that is directly related to this puzzle's theme, such as Hedy Lamar or the Bikini
Atoll, respectively. Enjoy ...
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