Today in Science History -
Even in this current age of ubiquitous computers
and cellphones (also computers), there is still ample reason to consider using
nomographs for presenting data and providing a hand calculation or conversion
resource. In days prior, nomographs were an indispensible tool for both design and
troubleshooting circuits. A huge number of nomographs can be found here on RF Cafe
as they appeared in vintage magazine articles. This 1946 issue of Radio-Craft presents
the first of a two-part tutorial on creating nomographs for any purpose, and uses
current, voltage, and resistance as an example. Their utility is not limited to
electrical and electronic topics, as many have been created for plumbing, hydraulics,
mechanics, chemistry, finance, aerodynamics, pneumatics, lighting, acoustics, and
I've even seen one...
Is it just me or does this seem like a moot
/ obvious arguement? "For anyone looking for an end-of-the-summer mind bender, this
might be one to consider.
Where does the terahertz (THz) spectrum range start? The subject came up during
a symposium last year, and it was covered here. Some researchers figure it starts
at 100 GHz. Others say it's 300 GHz. Suffice it to say, the debate is alive and
well - depending on who you talk to. Why should we care? For one, it helps to know
what’s what when it comes to spectrum, the idea being there's a finite amount in
the lower bands. Some day, somebody will come knocking for even more spectrum, and
these very high frequency ranges will come in handy when there's nowhere else to
go. For another, it's part of the grand plan for 6G, and even though it's early
days in a lot of ways for 5G..."
Navy electrical equipment is designed and
installed with every possible provision for the safety of the men who use it and
service it. But this does not completely
prevent injury to you and your shipmates or damage to equipment. Safety also
depends on the Electrician's training. To insure safety while standing watch or
working on a circuit, he must always work safely and observe safety precautions.
Men have been burned, electrocuted, or maimed for life because they became careless
in their work or failed to observe safety precautions. You were selected to be an
Electrician's Mate because of your intelligence, so use your brain to prevent accidents.
Injury and damage can be avoided by staying alert, exercising intelligence...
Teledyne Relays today announced availability
of a significantly expanded line of
50+ GHz coax switches, adding transfer switching, terminated, and normally-open
models to its product line-up. These join the CCR-50U SPDT DC-53 GHz failsafe/ latching
relay and CCR-39 SPnT DC-52 GHz latching coax relays that already enjoy wide acceptance.
In addition to excellent RF performance, the family offers the widest operational
temperature range (-55 to +85 °C), lowest weight and amongst the longest life (up
to 5 million actuator cycles) of any 50 GHz switches available today...
In this August 1963 adventure from Popular
Electronics magazine, teenage techno-investigators Carl Anderson and Jerry Bishop
use their home-brew sonar device to help the local sheriff nab a couple bank robbers.
The "Hydro Probe" mentioned in the article was a real product manufactured by the
Raymond Development Company of Watertown, Massachusetts (no longer in business).
By this time the duo were students pursuing electrical engineering degrees at Parvoo
University (a play on Perdue University, located in the boys' home state of Indiana).
New Scheme rotates
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If you need your company news to be seen, RF Cafe is the place to be.
TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
are available to provide temperatures between −100°C and +200°C for cryogenic cooling,
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Remember the early 1990s Teen Talk Barbie
where one of her phrases, "Math
class is tough!," caused a big kerfuffle because it ostensibly stereotyped girls
as being afraid of math? Maybe if Talking GI Joe (this 1967 version is the
one I had as a kid) also uttered a math phobia statement all would have been fine.
The truth is that a large portion of both girls and boys (and men and women) of
all ages break out in a cold sweat whenever the subject of math arises in print
or in a conversation. The ARRL goes to great lengths to help ease the math anxiety
of radio operators who are studying for a license exam. In this multi-part 1946
Radio−Craft magazine article, the authors attempt to assuage some of the
reluctance of readers to apply mathematics to their electronics hobby endeavors...
"Seeking a route to high-performance power
semiconductors, scientists in Japan have bonded
gallium nitride to a diamond substrate – the latter an insulator whose thermal
conductivity is many times that of copper or silver. 'The researchers succeed in
the direct bonding of diamond and GaN at room temperature, and demonstrate that
the bond can withstand heat treatments of 1,000°C, making it ideal for the high
temperature fabrication process of GaN-based devices,' according to Osaka City University,
home of the project. Unsurprisingly, attempts have already been made create a GaN-on-diamond,
using some form of transition or adhesion layer..."
Canadian website visitor Richard F.
sent me this photo of his "Log
Polar Plane" acetate stencil, circa 1958. As a collector of vintage of science
/ technical paraphernalia, he ran across this as part of one of his acquisitions.
"Computing Aids" is printed on it. I had never heard of the log polar plane, but
according to the Wikipedia entry, "In mathematics, log-polar coordinates (or logarithmic
polar coordinates) is a coordinate system in two dimensions, where a point is identified
by two numbers, one for the logarithm of the distance to a certain point, and one
for an angle. Log-polar coordinates are closely connected to polar coordinates,
which are usually used to describe domains in the plane with some sort of rotational
symmetry. In areas like harmonic and complex analysis, the log-polar coordinates
are more canonical than polar coordinates." The David Young, on the University of
Edinburgh website, explains, "Log-polar sampling is a spatially-variant image representation..."
It was a little difficult to make out the
shape within the
crossword puzzle grid from this December 1960 issue of Popular Electronics
magazine, so I got out my blue Crayon and filled in the hashed squares. It appears
to be a transistor schematic symbol. Unlike the weekly RF Cafe crossword puzzles,
not all of the clues and words are specifically related to science and engineering,
but a large percentage of them are. Admittedly, I have the advantage of a software
program to help place the words within the grid. Margaret LeFevre did not. Doing
it by hand is a lot more work. I can't imagine how the people who created the
New York Times' Sunday-size puzzles were able to do it without computer
Innovative Power Products (IPP) has over
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to visit their website and see how IPP can help you today.
"Why the Tube Shortage" was not a question
being asked by Radio−Craft magazine editor Hugo Gernsback, it was an explanation.
It is similar to the present day situation with the "Global Chip Shortage" in all
the headlines being blamed on the Wuhan Flu plandemic (sic) causing a worker shortage.
It has affected everything from the production of smart watches to kitchen appliances
to cars and trucks. In 1946, however, the cause of the
tube shortage was a multi-faceted ordeal according to investigative work by
Mr. Gernsback. Service shops were accusing tube manufacturers of favoring radio
production companies while radio production companies accused the tube manufacturers
of favoring service shops. The truth, ostensibly, was that the federal government
still laid claims to a large portion of tube manufacturing for post-war defense
needs, and at the same time labor strikes were crippling production lines...
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
"Visible light has been used to communicate
for centuries. Lanterns on ships and Morse code flashes allowed information to be
conveyed at a distance. But now there's a better way to use light to communicate
over even further distances and with far more accuracy: lasers. Launching in 2021,
Laser Communications Relay Demonstration (LCRD) is going to geostationary orbit,
where it will communicate with the ground at gigabit speeds. It's the agency's latest
step to get more data from space per downlink. Currently, most NASA missions use
radio frequency communications to send data to and from spacecraft. Radio waves
have been used in space communications since the beginning of space exploration
and have a proven track record of success. However, as space missions generate and
collect more data, the need for enhanced communications capabilities becomes paramount..."
ConductRF offers many lines of Lab &
Production RF Test solutions for DC to 18 GHz.
TEA80 series TESTeCON and TESTeLINK RF Cable lines feature standard connector
choices include straight male, female, and bulkhead, and right angle male. Standard
interfaces include type-N, TNC, SMA, 3.5 mm, and 2.92 mm. Phase stable
testing ±4° to 18 GHz, amplitude stable to ±0.2 dB to 18 GHz, max
power 170 W @ 18 GHz, flex life over 10,000 cycles, cable loss <0.330 dB/ft
@ 18 GHz, VSWR <1.30:1 (typical < 1.20:1). These cables can be purchased
directly from Digi-Key. ConductRF VNA series provides customers with reliable ruggedized
solutions for lab and production vector network analyzer testing. With options for
18, 26.5, 40, 50 & 70 GHz...
Narrow-band frequency modulation (NFM) was
a relatively new technology in 1947, having been advanced significantly during World
War II. Amateur radio operators were just getting their gear back on the air
after having been prohibited from transmitting for the duration of the war (see
"War Comes," January 1942 QST). Few were probably thinking about adopting
and exploiting new modulation techniques, but for those who were and recognized
FM as the path to the future of radio, QST published this fairly comprehensive
treatment of both frequency modulation (FM) and phase modulation (PM). Mathematically,
FM is the time derivative of PM. Both modulation schemes vary the carrier frequency
in some proportion to the baseband signal. Author Byron Goodman provides some insight
into the techniques...
Since 2003, Bittele Electronics has consistently
provided low-volume, electronic contract manufacturing (ECM) and turnkey PCB assembly
services. It specializes in board level turnkey
PCB assembly for design engineers needing low volume or prototype
multi-layer printed circuit boards.
Free Passive Components: Bittele
Electronics is taking one further step in its commitment of offering the best service
to clients of its PCB assembly business. Bittele is now offering common passive
components to its clients FREE of Charge.
Modelithics, the leader in providing simulation
models for RF, microwave, and mmWave devices is pleased to welcome
Dr. Ali Boudiaf to the company as Director of Lab Operations. Dr. Boudiaf
comes to Modelithics with 30 years of experience in the RF, microwave, and mmWave
engineering arena. In his new role at Modelithics, his responsibilities include
managing all aspects of lab operations as well as advancing Modelithics microwave
and millimeter-wave test system capabilities. Prior to joining Modelithics, Dr.
Boudiaf was the CEO and co-founder of Smart MedTech. He also previously worked at
ERZIA Technologies as Director of Amplifier Systems. Dr. Boudiaf's prior experience
also includes positions with Maury Microwave, Focus Microwaves, Agilent Technologies,
and ATN Microwave...
Television and radio facsimile machine electronics
technology was credited for aiding in the development of a new type of
scanning electron microscope (SEM) that could image the surface of opaque object
to a resolution of 100 angstroms (Å). The television contribution part of the technology
was precisely controlling a raster path for the electron beam. The facsimile part
was the knowledge of how to assemble a printed image from streaming data. It is
interesting to note that in order for an object to be imaged via SEM, its surface
must be electrically conductive. Accordingly, non-metallic objects like bugs, plants,
plastic, wood, etc., must receive a coating of metal by a process such as sputtering.
Doing so can leave a few atoms thick later without losing too much resolution due
to softening of features...