|
 • "640k [of RAM] ought to be enough for anybody." - Bill Gates, 1981
• "There is no reason anyone would want a computer in their home." - Ken Olson, president/founder
of Digital Equipment Corp., 1977
• "Heavier-than-air flying machines are impossible." - Lord Kelvin
• "Software is like entropy. It is difficult to grasp, weighs nothing, and obeys the second
law of thermodynamics; i.e. it always increases." - Norm Augustine
• "Counting in octal is just like counting in decimal, if you don't use your thumbs." -
Tom Lehrer
 everything RF is a product discovery platform for RF & Microwave Products/Services.
We currently have more than 344,923 RF & Microwave products from over 2281 companies
listed in 470 categories in our database and enable engineers to search for them
using our customized parametric search tool. Highlighted here is the
Butler Matrix,
which is an analog beamforming network that is used to feed the phased array
antenna elements and control the directions of beams. Many modern wireless
technologies used phased array antennas to provide...
 Plenty of intrigue still surrounds the July
2, 1937, disappearance of
Amelia Earhart in the South Pacific on her way to completing an
around-the-world flight. This article appeared two years prior to that fateful flight
proclaiming the soundness (no pun intended) of her onboard radio. Back in the day,
shortwave radio installations in aircraft required long wires trailing behind, particularly
for long distance requirements like flying from the U.S. mainland to Hawaii. Those
wires were a constant source of trouble due to destructive mechanical oscillations
while waving in the airstream, airframe damage due to striking during the haul in/out
procedure, and breakage. According to an article that appeared in the January 2015
edition of Smithsonian magazine, it is suspected that Earhart's antenna broke early
in her flight...
 In the midst of the transition from vacuum
tubes to semiconductors, this 1963 Radio-Electronics magazine infomercial
by Mallory offered guidance on
modernizing old selenium rectifiers with the latest silicon versions. This process,
commonplace at the time, symbolized the shift towards more efficient and compact
electronic components. The article provided a detailed walkthrough for replacing
these rectifiers in a standard TV voltage doubler circuit, recommending specific
models such as the Mallory VB500 or pairs of 1N2095's or A500's. It also cautioned
about potential increases in output voltage (B+) post-replacement, advising the
possible need for a dropping resistor. Furthermore, it highlighted that unchanged
B+ voltage could signal faulty filter capacitors, offering steps for their inspection
and substitution if needed...
 "In August last year Nokia and Axiom Space
announced they were working to equip the latter's next-generation lunar
spacesuits with 4G/LTE connectivity for the for NASA's Artemis III mission to
the moon. The idea is that arming the new spacesuit, called Axiom Extravehicular
Mobility Unit (AxEMU), with high-speed cellular-network capabilities means it can
support HD video, telemetry data and voice transmission over multiple kilometers
on the moon. This means the Artemis III crewmembers will then be able to capture
real-time video and communications..."
 Mrs. Helen McKee, XYL of W9ARK, knew exactly
what she was signing up for when she agreed to marry Mr. McKee. After all, she met
and got familiar with the guy over the air during some rag chewing sessions. This
story is a humorous (and true) account of what life can be like for the
spouses
of enthusiastic Ham radio operators. We all hope for such an understanding "significant
other." Melanie has certainly endured and supported a lot of my pastime endeavors
over the past 4-plus years. It's a short read, so take a break and put a smile on
your face...
 As a leading supplier of high-performance
made-to-order RF coaxial cable assemblies, ConductRF is excited to announce the
availability of our complete suite of
VITA 67 RF coaxial cable assemblies and connectors. In line with our commitment
to providing customers with superior flexibility and performance, ConductRF offers
the option to select from all leading VITA 67 connector brands, ensuring optimal
system compatibility and customization. VITA 67 solutions are widely used in military,
aerospace, and other high-reliability applications where precision RF signal transmission...
 English mathematician George Boole published
his "Formal Logic" syllogism system of deductive reasoning in 1847.
Fellow countryman Augustus De Morgan followed on Boole's work to develop the basic
combinational logic rules the AND gates, OR gates, and NOT (negation) operators.
What has become known as Boolean algebra and De Morgan's theorem forms the fundamental
foundation of everything related to digital logic. This second in a three-part series
from a 1974 issue of Popular Electronics introduces both concepts at a beginner's
level. Part 3 will present flip-flops and an overview of how all the parts come
together to build a simple computer...
 Being a long-time fan of John T. Frye's
"Carl & Jerry" technodrama™ series, I have been intending to attempt a contemporary
version which has a Ham radio theme. Its purpose, as with "Carl & Jerry," is
to encourage young people to adopt electronics as a hobby and even as a career,
while using Amateur Radio as an enticement. Ham radio offers practical experience
in electronic theory, fabrication, and operation in an environment that encourages
community service, mentorship, camaraderie, and self discipline. In the U.S., there
are approximately 760,000 licensed amateur radio operators; worldwide, the estimated
number is around 3,000,000. The American Radio Relay League (ARRL) and the International
Amateur Radio Union (IARU) track these statistics. This title of the series is,
for now anyway, "Calvin &
Phineas Hamming It Up," and the first adventure is called, "The Phantom QRM."
Call signs are fictitious, chosen to hopefully not step on someone's real call sign.
The boys' names derive from my grandson's name...
 There are probably few baseband and IF
delay lines these days that are constructed from a chain of inductor-capacitor
(LC) sections as described in this 1953 Radio-Electronics magazine article.
SAW and MEMS devices are the more likely choice for many reasons including cost,
weight, and volume savings. The preferred implementation of measured delays nowadays
would be in software after sampling with an analog-to-digital converter (ADC). There
are still applications for coaxial delay lines such as phase matching or adjustment
between system elements, and many companies offer custom designs with delay precision
in the tens of picoseconds. I once worked on part of a VHF/UFH transceiver unit
that used precise lengths of coax cable as part of a signal cancellation circuit
for enabling multiple radios to function in close proximity. I was not the designer...
 "New Street Research analyst Blair Levin
titled today's research note: On C-Band, Who Wins? Musk or Wireless? Right now,
he's giving the edge to wireless, but it's early days. Is it time to pop the champagne?
Not quite, analysts say. The wireless industry might have won the first round in
the
upper
C-band kerfuffle, but given that Elon Musk is the challenger, nothing is a done
deal. What are we talking about? Get the popcorn because this will take a minute.
Earlier this week, the wireless industry, namely CTIA, cheered FCC Chairman Brendan
Carr's move to launch a Notice of Inquiry (NOI)..."
 Channel Master is one of the few television
and FM radio antenna companies that has survived the evolution from over-the-air
(OTA) broadcasting to cable-based and then Internet-based broadcasting. Up until
around the end of the last century - which is incredibly two decades ago - a large
number of people still relied on rooftop and set-top antennas for program reception.
Airwaves continued to get more crowded both due to additional stations being built
and the ambient noise level increasing due to many other lower power devices in
use. An increasing number of manmade obstacles that blocked and/or reflected signals
resulted in many more low signal strength pockets and areas plagued by multipath
signal variability compounded the problem...
• €1B
European Chips Act Money for Infineon's Dresden Fab
• AM
Radio Mandate Costs Low for Automakers
• Dayton
Hamvention 2025 Award Winners
• FCC's Carr to Persuade Allies on new
Subsea Cable Regs
• AM
Radio for Every Vehicle Act up for Vote
 Color TV has reached nearly 5 million American
homes, but many viewers complain about inaccurate colors due to
chroma-phase differences among networks, stations, and cameras. This results
in annoying hue changes, making it difficult for viewers to adjust the Hue or Tint
control for accurate flesh tones. This 1966 Radio-Electronics magazine article suggests
three possible solutions to this problem, emphasizing the need for precise phase
agreement among all components of the color TV system. Solving this issue could
encourage more people to adopt color TV technology, as the annoyance of inconsistent
colors is one of the last reasons the public has found for not making color-TV ownership
unanimous. Still plaguing the color TV industry is powerful x-rays emanating from
the high...
 "A research team from the University of
Science and Technology of China (USTC), part of the Chinese Academy of Sciences,
along with its partners, has made significant progress in random quantum circuit
sampling using Zuchongzhi-3 - a superconducting quantum computing prototype equipped
with
105 qubits and 182 couplers. Zuchongzhi-3 operates at an astonishing speed,
performing computations 1015 times faster than the most powerful supercomputer available
today and one million times faster than Google's latest published quantum computing
results. This achievement..."
 Acrylic wall-to-wall carpeting really came
into vogue in the late 1960s to early 1970s - just in time for the arrival of miniaturized
microelectronics (is that redundant or just superfluous?). Gate widths were being
shrunken rapidly as the birth of the Moore's Law era was in its infancy (born in
a 1965 paper written by Intel engineer and co-founder Gordon Moore). The result
was copious quantities of
electronic gadgets being zapped when the unsuspecting user would
walk across the Van de Graaff generator in the form of floor covering and reach
for a dial or switch. A couple thousand volts could easily build up on a body clad
in lime green polyester pants (remember the era), then fzzzzt, there goes the clock
radio or AM/FM tuner. Vacuum tube circuits from a decade earlier...
 BroadWave Technologies showcases
600 Ω Impedance Terminations. Model 592-401-005 has a DC-1 GHz operating
frequency range and is rated 5-Watts average power at 25°C. The maximum VSWR is
1.20:1 and the RF connector is N male. Developed to simulate load flow on a data
bus these terminations are useful in simulating emergency operation conditions.
Applications include installations with elements that vary over time such as electric
vehicle charging stations. Delivery for up to 25 pieces is from stock to 1-week
ARO. Custom impedance and other connector types are also available...
 We hear and read a lot in the news about
the electronic
surveillance carried out by governments - on both foreign entities and civilians.
If you think this is a phenomenon that has only existed since the age of cellphones
and the Internet, you might be interested in this article that appeared in a 1945
issue of the ARRL's QST magazine. Long before the entire textual content
of the Encyclopedia Britannica could be carried on a USB stick in your pocket -
and access virtually all the information in the world on your iPhone, engineers
were developing recording media to facilitate the capturing and later analysis of
over-the-air and wired communications. They wanted both encrypted and unencrypted
conversations. The National Archives has a huge store of magnetic tapes, vinyl discs...
 Innovative Power Products has been designing
and manufacturing RF and Microwave passive components since 2005. We use the latest
design tools available to build our baluns, 90-degree couplers, directional couplers,
combiners/dividers, single-ended transformers, resistors, terminations, and custom
products. Applications in military, medical, industrial, and commercial markets
are serviced around the world. Products listed on the website link to detailed mechanical
drawings, electrical specifications, and performance data. If you cannot find a
product that meets your requirements on our website, contact us to speak with one
of our experienced design engineers about your project.
 Even though this article was written more
than half a century ago, the fundamentals of
protecting relays against interference from either internally
generated or externally generated noise haven't changed. Sometimes a datasheet will
recommend protection and noise suppression techniques, and when that is that case,
the manufacturer's advice should be followed (unless you have a really good reason
to deviate, possibly voiding a warranty). When you find yourself on your own with
the design, whether a new creation or modifying an existing circuit, use this article
and the very comprehensive table of application examples. This reminds me of the
early 2000's when the RFIC company I worked for was in a frenzy developing ways
to protect the inputs and outputs of their devices...
 "The use of
terahertz waves, which have shorter wavelengths and higher frequencies than
radio waves, could enable faster data transmission, more precise medical imaging,
and higher-resolution radar. But effectively generating terahertz waves using a
semiconductor chip, which is essential for incorporation into electronic devices,
is notoriously difficult. Many current techniques can't generate waves with enough
radiating power for useful applications unless they utilize bulky and expensive
silicon lenses. Higher radiating power allows terahertz signals to travel farther.
Such lenses..."
 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
new
Multi-Channel SMPS Cable Assemblies (WMCS Series) provide a wide range of multiple
coax connectors and flexible cable assemblies with a choice of 26.5, 40, 50 &
67 GHz configurations based on precision array design and superior high frequency
cabling solutions. These products consist of high performance flexible assemblies
which can be bundled in housings (2, 4, & 8 channels) and the interface to board
is compression type which provides lower total cost of testing by avoiding costly
soldering components...
 This full-page advertisement by
CBS Tubes caught my eye because of the vast array of vacuum tube
shapes and sizes. It appeared in a 1958 issue of Radio & TV News magazine.
Most people, even back in the era of tube-based electronic equipment, think of the
standard 12AX7 type rounded top, cylindrical glass package with a plastic or phenolic
base and some metal pins sticking out of the bottom. Television and radio sets were
full of them, and those are what you or your parents or grandparents would yank
from the chassis and take to the local drug store or electronics shop to plug into
the big tube tester that was commonplace back then. However, as this photo shows
there was a great variety of special glass and inner electrode configurations. If
you have ever attended the MTTS (IMS) show, you might have seen the equipment display
provided by the National Electronics Museum...
 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.
 On April 20, 1964, AT&T introduced the
Picturephone at the New York World's Fair, enabling coast-to-coast video communication.
The device, which featured a 4-3/8" x 5-3/4" screen and push-button controls allowing
users to display themselves, others, or nothing at all, went into commercial service
on June 24 with public booths in New York, Washington, and Chicago. The article
notes that the concept of video telephony was first imagined in Hugo Gernsback's
1911 science fiction novel "Ralph 124C 41+," where it was called the "Telephot."
While initially expensive ($16-$27 for 3 minutes depending on cities connected),
the Mr. Gernsback, in this 1964 editorial, predicts the technology would eventually
become more affordable and evolve to include features like language translation,
3D capabilities...
|
 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...
 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
assistance!
 Many people end on RF cafe as a result of a Google
(or other) search about electronics, so even though regular visitors might find this
primer on
Ohm's law to be redundant review, it will be valuable to the aforementioned people.
Electronics technology has moved forward at lightning speed in the last century, but
the fundamentals of Ohm's law remain unchanged. Indeed, we would be in trouble if voltage
no longer equaled the product of current and voltage (E = I x R).
National Radio-TV News magazine was published monthly by National Radio Institute,
a correspondence school that did business from 1914 through 2002. A bonus electronics-themed
comic is included...
 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...
 Radio-Electronics magazines' "Service
Digest" column regularly reported on issues relevant to the electronics servicemen
who repaired radios, television sets, phonographs, recorders, and similar items
- often in the customers' homes. Then, as now, professionalism and courteous behavior
was often rewarded with word-of-mouth referrals to friends and relatives, resulting
in new business opportunities. An interesting topic also included was the need to
observe extreme caution when working around TV tubes (CRT's) not just because of
the lethally high voltages present, but because of the
danger of tube implosion and the resulting scattering of glass shards. An example
given is that due to standard atmospheric press of 14.7 lbs/in2 on the outside of
the evacuated volume, a 17-inch screen CRT tube supports a total pressure of 3,322
pounds, or 1.66 tons...
 Except under special circumstances, the Federal
Communications Commission (FCC) does not conduct much frequency monitoring activity.
I know first-hand that even when a report of
radio frequency interference (RFI) is made to them, you will be told to figure
out the source on your own and then get back to them*. There have been a lot of
news items lately where the FCC has levied heavy fines on Ham operators found to
be in violation of the regulations, and usually not because of independent complaints.
This article from a 1956 edition of Popular Electronics magazine relates some of
the cases experienced by guys in the FCC Field Engineering and Monitoring Bureau's
according to "Negotiated Rulemaking Committee" (NRMC - now defunct) records...
 The Hewlett Packard
HP-25 programmable scientific calculator was initially introduced in 1975 at
a retail price of $195. It was considered ground-breaking because of its size and
the number of functions available. Thirty pushbutton keys including two second function
keys provided more than seventy-two overall types of inputs, most of which could
be incorporated in program steps (up to 49 operations). This was not HP's first
programmable calculator, but the price point put it in reach of hobbyists and school
kids. The original model would lose its program at power down, but the HP-25C, which
came out in 1976, had battery-backed memory (called "continuous memory by HP) that
was retained even when turned off. By the time this product review appeared in a
1976 issue of QST magazine, the price had dropped to around $135. Here is the HP
Museum entry for the HP-25 calculator. A functional HP-25 calculator can be purchased
on eBay...
 Here is an unusual twist in waveform recognition
presented by Radio-Electronics' and Popular Electronics' quizmaster,
Robert Balin. If you happen to be a former analog television repairman, then you
will probably recognize the answers based on your many years of diagnosing faulty
horizontal or vertical
sweep circuits. If not, then you might need to strain the "little gray cells"
a bit, as Agatha Christie's premier sleuth Hercule Poirot might say. The instructions
say to assume that if you choose the horizontal sweep sawtooth to be the errant
signal, then assume the vertical sweep sawtooth is correct, and vice versa. Right
off the bat, waveform 8 is unique enough to easily identify the sweep that would
produce it since only one has two repeating components. Most of the others can be
readily deduced, too, by mentally following the x and y points as the "correct"
sweep...
 As with my hundreds of previous
engineering and science-themed crossword puzzles, this one for January 12, 2020,
contains only clues and terms associated with engineering, science, physical, astronomy,
mathematics, chemistry, etc., which I have built up over nearly two decades. Many
new words and company names have been added that had not even been created when
I started in the year 2002. You will never find a word taxing your knowledge of
a numbnut soap opera star or the name of some obscure village in the Andes mountains.
You might, however, encounter the name of a movie star like Hedy Lamarr or a geographical
location like Tunguska, Russia, for reasons which, if you don't already know, might
surprise you.
 Radio & Television News editor
Oliver Reed wrote in this 1955 issue about the "flattening" of electronics - including
both individual components and overall assembled products. He described a large
screen, wall-mountable television system with built-in flat stereo electrostatic
speakers. "The so-called 'picture
on the wall' television screen has also received widespread publicity although
such a screen is not yet commercially available. In this system, a flat screen is
connected to the TV receiver by means of a cable, and the picture is formed on the
screen electronically." That is a lot like a large flat LCD or LED monitor being
fed by an HDMI cable from a computer. Mr. Reed also writes of a magnetic tape
video playback system akin to what eventually became the VHS / VCR. Evidently the
concept of an optical-based storage medium like the DVD and Blu-ray disk was too
far out of the realm of possibility...
 August 1962 was a good month for lovers of
nomographs and infographics. Electronics World magazine published three
articles feeding the mania, including this one, Sound | Audio | Music Infographic,
and Coil-Winding Charts. All make good printed references to keep on-hand. One nomograph
converts the ratio of two power levels (in watts, milliwatts, etc.) to equivalent
decibels of gain. It can also be used to find the unknown power level if one is
known and the gain in dB is known. The other nomograph facilitates graphically calculating
voltage or power based on the source resistance (assumed to have only real components;
i.e., no complex values). If you are not sure how to keep units constant for voltage,
power, and resistance (milli, micro, etc.), calculate using the base units and then
convert afterward...
 Most regular RF Cafe visitors will probably
not be too interested in this 1960 Popular Electronics magazine article,
but there are a lot of people who build and/or repair vintage radio gear and search
the Internet for helpful information. Having built a couple
crystal radio sets as a kid, I've always been amazed at how a few picowatts
of RF energy can be received, processed, and heard through an ear plug without the
need for external power from a battery. Speaking of crystal radios, I remember one
time while working as an electrician in Annapolis, Maryland, (prior to entering
electronics) I had a telephone handset for use in communicating with other electricians
in a building I was wiring, and it picked up the local AM radio station. A pair
of the old style handsets with carbon microphones would, with the help of a single
'D' cell in series, function as a very acceptable intercom system using two standard
electrical wires between them...
 The synchronous motor in my vintage
General Electric Model 7-4305C Roll-Down Number Clock Radio began making grinding
noises. An investigation showed it was the 3.6 rpm AC synchronous motor. It
was tightly sealed, so I carefully drilled an 1/8" hole in the housing (being sure
not to get metal debris inside), inserted a few drops of 3-in-1 oil and shook it
around, then re-installed it, plugged it back in and voila - no more noise! (see
photos). BTW, if you can even find these motors on eBay, they cost more than an
entire clock-radio. Fortunately, I found another 7-4305C at a yard sale so I have
a spare...
 "Xeledop" is the Word of the Day for October
31; use it often. Xeledop is an acronym for "transmitting elementary dipole with optional
polarity." Nope, I've never heard of it, either. The
Xeledop (probably pronounced "zeh'-le-dop") is an air-towed transmitter that
flies a pre-planned path around the ground-based antenna under test (AUT) whose
radiation pattern is being measured. The circular power level plot at the bottom
of the page shows the results of an actual test flight. In this application, a
high frequency (HF, 3-30 MHz) transmitter is towed behind an airplane like
target drone while it broadcasts signals at eight distinct frequencies toward
the AUT, while the downstream receiver records power levels. The pilot flies on
the surface of an imaginary hemisphere to maintain a constant radius from the
antenna. Ground equipment tracks the aircraft azimuth and slant range is
calculated using aircraft altimeter data and measured elevation angles...
 Even in this time of readily available computers
(including your smartphone) and printers, having a set of
rubber stamps for common electronics symbols would be pretty handy; there are
some Neanderthals among us who still use pencil and paper on occasion. Simpler symbols
like resistors and capacitors are easy enough to sketch by hand, but something like
a dual gate MOSFET with diode protection can take some time to produce legibly.
Common connector types like the DB signal/power series and some RF kinds (BNC, SMA,
etc.) would be useful, as would a set of oft-used logic gates for the digital designers.
The set shown here in a 1953 edition of Radio-Electronics magazine includes a handful
of vacuum tube types which would have taken some time to draw by hand, and a few
other symbols...
 Most of us probably never give much thought
to how vulnerable we could be in a lawsuit related to our professional activities
- until it's too late. That is particularly true if you are not directly involved
in the sales or service business. Even when it is reasonable to believe that there
is no way a jury or judge could
find you liable for a charge levied against you, the skill of
a talented lawyer and/or whims and prejudices of judges and/or jurors can doom you.
Although a bit dated, the legal cases cited in this Radio-Electronics article
give a little insight into why you would do well to give some thought to what the
consequences of your actions and/or statements might invite if someone decides you
have offended him or her. Remember that settled legal cases are regarded as precedence...
 I when I originally posted NIST Technical
Note 1297, it had the name "Essentials
of Expressing Measurement Uncertainty." Since that time, the NIST website changed
its link to the updated version which now goes by the title of "Guidelines for Evaluating
and Expressing the Uncertainty of NIST Measurement Results." It includes a lot of
new data; in fact, it has been nearly totally re-written. This is a valuable reference
for anyone who needs to understand the proper method for calculating measurement
uncertainties. Preface to the 1994 Edition The previous edition, which was the first,
of this National Institute of Standards and Technology (NIST) Technical Note (TN
1297) was initially published in January 1993...
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...
 Here is the electromagnetic wave section
of the "Wireless Networking in the Developing World," book (open source). "Wireless
communications make use of
electromagnetic
waves to send signals across long distances. From a user's perspective, wireless
connections are not particularly different from any other network connection: your
web browser, email, and other applications all work as you would expect. But radio
waves have some unexpected properties compared to Ethernet cable. For example, it's
very easy to see the path that an Ethernet cable takes: locate the plug sticking
out of your computer, follow the cable to the other end, and you've found it! You
can also be confident that running many Ethernet cables alongside each other won't
cause problems, since the cables effectively keep their signals contained within
the wire itself. But how do you know where the waves emanating from your wireless
device are going..."
 The manned space program has unarguably provided
mankind with many new and innovative tools, medicines, electronics, materials, physics,
materials, appliances, and mathematics. Known officially as "spinoffs," products
include items like the portable heart defibrillator unit, the portable vacuum cleaner,
freeze-drying food processors, powdered lubricants, memory foam, quartz clocks and
battery-powered tools. Many
NASA inventions have not found an application in your basement
or garage, however, because their purpose is too specialized. Take, for instance,
the ZeRT, or Zero Reaction Tool...
 "Use it up... Wear it out... Make it do...
Or do without" - what a great slogan! It was coined by the
War Advertising Council during World War II to promote the dual need to
conserve scarce resources and to help keep prices down by not generating excess
demand. Most of us have seen videos or read articles about neighborhood materials
collection efforts to round up old tires, scrap metal, glass, tools, electronics
equipment, cloth and clothing, and many other items that could be recycled for used
directly in the war effort. There was also an undertone of not abetting attempts
by opportunists to profiteer off the war. Government policy did what it could to
control the economy by instituting severely progressive income taxes and price controls
(that way only the ultimate insiders could get rich). After 11.3% and 7.6% inflation
rates... |
