See Page 1 |
2 |
3 |
4 | of the November 2023 homepage archives.
Thursday the 30th
Ask anyone who has ever asked me to fix
something electrical or electronic and they will tell you my motto on such things,
born of extensive experience, is that the vast majority of the problems are caused
by poor electrical contacts of one form or another. The culprit can be a dirty or
broken connector, a cold or broken solder joint, a dirty potentiometer (contact
between wiper and resistor), etc. I have repaired everything from ceiling lights,
to car starters, to kitchen appliances, to large screen TVs simply by finding and
repairing connections. When possible, I always do a final cleaning with isopropyl
alcohol and then spray with a silicon contact protector. This
Contact Shield product from Channel Master would be a good choice. I can honestly
say I cannot think of a single instance where the restored connection failed again.
Of course sometimes it is not that simple, but enough that my initial approach to
troubleshooting - unless a broken or burnt component is immediately apparent - is
to unplug and inspect connectors (then plug-unplug-plug to wipe contacts clean),
flip switches on-off a few times while applying various directional forces (left-right,
up-down, twisting), tugging on wires, etc. People's eyes light up in amazement when
a sophisticated piece of equipment starts working after doing so. Then, I me
This is the
electronics market prediction for The Netherlands, circa 1966. It was part of
a comprehensive assessment by the editors of Electronics magazine of the state of
commercial, military, and consumer electronics at the end of 1965. Philips, headquartered
in Amsterdam, was singled out as a prime mover for the country. Established in 1891,
Philips is still today a major economic contributor for The Netherlands. Electronics'
end-of-year issue published its prognostication for Europe as a whole as well as
for many individual countries. It also attempted to assess the Soviet Union's (USSR)
electronics industry...
"Surrey University has been awarded £250,000
from the UK Space Agency to develop a new telescope that aims to boost understanding
of space weather and make flying safer. The Surrey team is developing prototypes
for a new
High Energy Proton Telescope (HEPTEL), which aims to measure the radiation caused
by solar flares in space before it reaches the Earth's atmosphere. According to
the scientists, HEPTEL will monitor extremely high energy protons, the dominant
particle type from solar events which can stop electronic devices from working properly
once they penetrate the atmosphere. Systems on aircraft are said to be more at risk
due to their altitude. 'Given the ever-increasing quantity of electronics on-board,
future aircraft will need to be designed to cope with intense events, so we need
research like this to enable..."
This vintage Heathkit HW-5400 HF SSB Transceiver
kit showed up on eBay. I have been saving the images of these unbuilt kits in order
to preserve the history. The constantly growing list is at the lower right. The
HW-5400 covers the 80- through 10-meter bands as well as the 10 MHz WWV frequency
reference signal and the WARC bands. A video tour is posted below. A Web search
on the Heathkit HW-5400 HF SSB Transceiver shows mixed reviews. Some people loved
it, and others thought it was the worst transceiver Heathkit ever put out. Of course
that's the way it is with most things. In the case of kits, a lot depends on the
skill of the builder, because even the most proficient operator and assembler of
system level parts is not necessarily a great builder and/or tuner...
Before there were side-view neon numerical
indicator vacuum tubes there were top-view neon numerical indicator vacuum tubes.
Nixie tubes and pixie tubes were featured in "Readouts
and Counter Tubes" in the October 1959 issue of Electronics World magazine.
At the time, most were top-view designs whose size was restricted by the diameter
of the tube (typically about 0.8"). Switching to a side-view format did not enable
the overall width to increase much, but the aspect ratio permitted taller displays
with characters that appear as normally seen (rather than being squashed in height).
This advertisement in a 1965 issue of Electronics magazine for numerical indicator
tubes from Raytheon were likely some of the first side-view models available from
any manufacturer...
One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4 million pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 280,000
per year (in eight locations on each page, with >17,000 pages). That's pretty
good exposure for $300 per month. Some companies have expressed an interest in being
able to manage their advertising accounts themselves a la the Google AdSense program...
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
procedures.
Wednesday the 29th
The January 1967 instance of Radio-Electronics
magazine's "What's
Your EQ?" challenge contains only two puzzles. The first is a variation on the
classic resistor mesh wherein a matrix of series and parallel resistors, all of
a common value (10 Ω), are wired together, and your job is to determine what
total resistance would be measured between the indicated two points. Author E.D. Clark
implicitly suggests taking a good look at the schematic to simplify it before diving
into it with circuit analysis equations. Maybe cross your eyes a bit and cross-focus
like you do with those 3D images that were popular a couple decades ago. You'll
be amazed (see what I just did there?) at how simple it is to calculate the equivalent
resistance. The second puzzle takes a bit more work. No restrictions are placed
on what additional components can be inside the boxes. To clarify, if the top switch
and bulb are labeled "A" and the bottom one "B," then switch "A" switch independently
controls (on or off) only bulb "A" and switch "B" switch independently controls
(on or off) only bulb "B." The third wire mentioned for a simple connection would
be a common point for the current flow...
"It is estimated that 95% of the planet's
population has access to broadband internet, via cable or a mobile network. However,
there are still some places and situations in which staying connected can be very
difficult. Quick responses are necessary in emergency situations, such as after
an earthquake or during a conflict. So too are reliable telecommunications networks
that are not susceptible to outages and damage to infrastructure, networks can be
used to share data that is vital for people's well-being. A recent article, published
in the journal Aerospace, proposes the use of
nanosatellites to provide comprehensive and stable coverage in areas that are
hard to reach using long-range communications. It is based on the bachelor's and
master's degree final projects of Universitat Oberta de Catalunya (UOC) graduate
David N. Barraca Ibort. The number and financial cost of extreme weather events
has constantly increased in recent decades according to the World Meteorological
Organization (WMO). Climate change has vastly increased the likelihood of climate
disasters occurring all over the planet. However, thanks to improvements to emergency
and early warning services, the increase in extreme events has not led to an increase
in the number of victims..."
One of the major advantages of the age of
powerful personal computers - be they in the form of desktop systems, tablets, or
smartphone apps - is that for most computation-intensive tasks there only needs
to be one or maybe at most a few people smart enough to know how to do them. Everyone
else who has to perform the task just needs to be able to input the proper parameters
to ensure a useful output. That is a significant statement, because in the days
before ubiquitous computer availability and incredible computing power, highly capable
engineers, scientists, analysts, and mathematicians either had to be on staff or
an expert external resource was used for difficult and/or time-intensive tasks.
Over time, fewer and fewer people are needed to produce very precise and reliable
results. In many ways, other than the creative intuition involved in concept, creation,
and execution, a large part of the product design and planning phases have been
automated with the help of very capable software. This 1964 Electronics
magazine article about plotting of
satellite ground coverage maps is a good example...
Anatech Electronics 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. Three new
filters have been announced for November 2023: a very nice looking 250-500 MHz
tunable bandpass filter with N-type female connectors and passband insertion loss
of 1.0 dB, a 312.5 MHz cavity bandpass filter with an insertion loss of
1.0 dB and a rejection of 80 dB from 425-1000 MHz, and a 3400 MHz cavity
bandpass filter with a 1000 MHz pass band and a rejection of 40 dB at
both 2700 MHz and 4100 MHz. Custom RF power filter and directional couplers
designs can be designed and produced with required connector types when a standard
cannot be found, or the requirements are such that a custom approach is necessary...
When the concept of radio refrigerators
was presented in a 1933 edition of Radio-News magazine, it was not quite
what has become reality today. At the time, the
Radio Electrical Exposition had recently been held in Madison Square Garden
and the world was just getting used to the miracle of radio waves - and refrigerators
for that matter. Radio-refrigerators never did make their way into the consumer
market. Fast-forward 80 years and now we're seeing the advent of radio-refrigerators
re-emerge, only in a completely different format. This time, rather than playing
shows from local commercial broadcast stations, these appliances are communicating
with Wi-Fi routers to allow owners to check on status and contents from remote locations.
In other news, the editors report on a scheme to use a remote-controlled airplane,
signaled by a Tesla spark gap transmitter, to drop bombs inside tornados in order
to break up and stop their destructive presence (that drawing of a low-wing, single-engine
monoplane that looks a lot like a Piper Cherokee, was way ahead of its time). There
is also a photo of Major Armstrong's original lab notebook sketch of his idea for
a regenerative receiver circuit...
With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils available for RF, analog, and digital system and schematic
drawings! Every stencil symbol has been built to fit proportionally on the included
A-, B-, and C-size drawing page templates (or use your own page if preferred). Components
are provided for system block diagrams, conceptual drawings, schematics, test equipment,
racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1
scale so that measurements can be made directly using Visio built-in dimensioning
objects. Page templates are provided with a preset scale (changeable) for a good
presentation that can incorporate all provided symbols...
Amplifier Solutions Corporation (ASC) is
a manufacturer of amplifiers for commercial & military markets. ASC designs
and manufactures hybrid, surface mount flange, open carrier and connectorized amplifiers
for low, medium and high power applications using Gallium Nitride (GaN), Gallium
Arsenide (GaAs) and Silicon (Si) transistor technologies. ASC's thick film designs
operate in the frequency range of 300 kHz to 6 GHz. ASC offers thin film
designs that operate up to 20 GHz. ASC is located in an 8,000 sq.ft. facility
in the town of Telford, PA. We offer excellent customer support and take pride in
the ability to quickly react to evolving system design requirements.
Tuesday the 28th
Some of the earliest
printed circuit boards were literally printed onto a ceramic substrate using
silk-screening techniques. For that matter, silk cloth was used as the pattern mask;
hence the name silk-screen. A paste of silver particles was squeegeed through the
mesh, and the resulting circuit pattern was fired in an oven to solidify and adhere
the metal to the substrate. Holes were then drilled to accept component leads. After
inserting the leads through the holes, hand-soldering completed the assembly. It
was a game-changing technology. Not only was time and space saved and a more robust
product the result, but the process eliminated miswiring and made tracing out interconnections
much simpler when troubleshooting. According to this 1946 Popular Science
magazine article, the motivation for developing this technique was the proximity
fuse during World War II. Ditto for the tiny "peanut tubes" used. Necessity
is the mother of invention, as the saying goes...
This vintage
Heathkit
IM-104 Solid-State Voltmeter kit showed up on eBay. Although I only own a couple
Heathkit items, I have been saving the images of many unbuilt kits in order to preserve
the history. They regularly appear and disappear on eBay all the time - some models
more than others. One of the earliest instances of the IM-104 Solid-State Voltmeter
being offered for sale was in the Spring 1976 Heathkit catalog (p54), at a cost
of $94.95 ($504.55 in 2023 money per the BLS) in kit format, or $149.00 full built
and tested. That was/is a lot of cash to lay down for a multimeter that measures
AC/DC voltage and current, and resistance. However, the alternative if you needed
a high input impedance instrument, this was still cheaper than buying a vacuum tube
voltmeter (VTVM), and it is much smaller, lighter weight, and portable due to being
powered by batteries (a D cell and four AA cells). An article like "The Case for
the Transistorized Multimeter" was evidently deemed necessary in the 1968 issue
of Popular Electronics magazine to convince the VTVM faithful that the
newfangled DMM would make their lives better...
Electronics magazine editor Lewis H.
Young dedicated a series of issues in 1965 to reporting on the state of electronics
research and production in Japan. The December 13 edition had many articles on the
subject. The world was still in the early phase of a major transition from vacuum
tubes and discrete components to transistors and integrated circuits. Japan was
at the leading edge of that effort - and it was very successful. Ample evidence
of the not-quite-there-yet status of the transition is all the advertisements in
this edition of the magazine. Products showcased by manufacturers were discrete,
not integrated - that applies to both electronic and mechanical subjects. When you
look at those components and assemblies, you get a feel for what made them work
because the individual parts are in view. Many modern products are integrated into
packaged and tested subassemblies that are ready to be integrated into higher level
products. High performance, high functionality products can thereby be developed
and produced at a blazing speed. Both the professional and the DIY communities have
benefitted greatly...
"NASAs
Deep Space Optical Communications (DSOC) experiment has beamed a near-infrared
laser encoded with test data from nearly 10 million miles (16 Mkm) away - about
40 times farther than the Moon is from Earth - to the Hale Telescope at Caltech's
Palomar Observatory in San Diego County, California. This is the farthest-ever demonstration
of optical communications. Riding aboard the recently launched Psyche spacecraft,
DSOC is configured to send high-bandwidth test data to Earth during its two-year
technology demonstration as Psyche travels to the main asteroid belt between Mars
and Jupiter. NASA's Jet Propulsion Laboratory aboard Psyche capable of sending and
receiving near-infrared signals - locked onto a powerful uplink laser beacon transmitted
from the Optical Communications Telescope Laboratory at JPL's Table Mountain Facility
near Wrightwood, California. The uplink beacon helped the transceiver aim its downlink
laser back to Palomar (which is 100 miles, or 130 kilometers, south of Table Mountain)
while automated system..."
Most of the earliest automobile radios had
the electronics mounted in a metal box mounted under a seat or in the trunk, separate
from the dashboard tuning dial. Ditto for the power supply. The bulk and weight
prevented colocation. This 1937-vintage
Ford-Philco model F-1440 radio is one for which I was able to find a couple
examples for sale on eBay. One claims to be fully functional and the other is in
pretty rough shape. The August 1937 issue of Radio-Craft magazine included
the schematic and tuning procedure for it. If your era car or truck came without
a radio and you would like to finally upgrade, this is your opportunity ;-)
Banner Ads are rotated in all locations
on the page! RF Cafe typically receives 8,000-15,000 visits each
weekday. RF Cafe
is a favorite of engineers, technicians, hobbyists, and students all over the world.
With more than 17,000 pages in the Google search index, RF Cafe returns in
favorable positions on many types of key searches, both for text and images.
Your Banner Ads are displayed on average 280,000 times per year! New content
is added on a daily basis, which keeps the major search engines interested enough
to spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. If you need your company news to be seen, RF Cafe is the
place to be...
Alliance Test Equipment sells
used / refurbished
test equipment and offers short- and long-term rentals. They also offer repair,
maintenance and calibration. Prices discounted up to 80% off list price. Agilent/HP,
Tektronix, Anritsu, Fluke, R&S and other major brands. A global organization
with ability to source hard to find equipment through our network of suppliers.
Alliance Test will purchase your excess test equipment in large or small lots. Blog
posts offer advice on application and use of a wide range of test equipment. Please
visit Allied Test Equipment today to see how they can help your project.
Monday the 27th
These rather nicely done paintings celebrating
the "Westinghouse
Centenary" appeared in a 1946 issue of Popular Science magazine. The
centenary marked the 100th year since the birth of George Westinghouse, not the
company. We electrical and electronics types know Westinghouse Electric Corporation,
founded by George Westinghouse in 1886, as a company that makes electrical distribution
equipment, electronics products and systems, household appliances, industrial motors
and generators, jet engines, and other high tech products. However, George Westinghouse
was famous first for his locomotive air brake design. He teamed up with Nikola Tesla
to battle Thomas Edison over the superiority of AC over DC for building a large
scale distribution system. The caption of one picture mentions that DC systems could
only cover 16 square miles. Line losses due to high currents dissipated a large
part of the power. AC allowed voltages to be cranked way up to keep current down.
Unlike DC, AC can be efficiently and economically transformed up and down. However,
modern principles are allowing high voltage direct current (HVDC) to be implemented
from generation plants to AC substations...
Congress was breathing hard down the neck
of NASA while Ranger 6 was being prepared for its
surveillance mission to the lunar surface. In 1962, Ranger 3, the first
to carry a TV camera, went into orbit around the sun after missing the moon. Ranger 4
(dubbed "Brainless I") impacted the moon but did not send back any data. And Ranger 5
lost power after launch and missed the moon by about 450 miles. Time was running
out to collect data for use in fulfilling the challenge issues by President John
F. Kennedy on May 25, 1961, to "...commit itself to achieving the goal, before
this decade is out, of landing a man on the Moon and returning him safely to the
Earth." That challenge was successfully met by the Apollo 11 mission partially
on July 21st, 1969 by landing Neil Armstrong and Buzz Aldrin on the moon, and then
fully on July 24th when they (Armstrong, Aldrin and Michael Collins) returned safely
to Earth. Ranger 6 unfortunately ended in failure on February 2nd, 1964, when
its TV camera did not return any images...
"A team of UK companies led by Stratospheric
Platforms Limited (SPL), a Non Terrestrial Networks telecoms developer, has won
a contract trialing advanced
airborne 5G connectivity from a Britten-Norman Islander. Aircraft manufacturer
Britten-Norman will be providing key design and trials support for the project,
with Marshall Futureworx providing cooling systems technology. SPL is pioneering
the concept of using a High-Altitude Platform (HAP) with airborne antenna to provide
wide scale coverage of high performance 5G from the stratosphere. The goal of the
project is to deliver an unmanned, liquid hydrogen-powered aircraft, designed with
a 56-metre wingspan that will, due to its lightweight structure and significant
power source, enable a flight endurance of over a week. The first phase of the contract
will see SPLs 5G airborne phased array integrated to a Britten-Norman Islander,
with flight trials..."
The
Silvertone brand of radios was manufactured for Sears, Roebuck & Company
by Colonial Radio. This particular mid-1930s Model 4488 that covered broadcast,
shortwave, and police bands was very popular, and the Radio Service Data Sheet published
in the June 1937 issue of Radio-Craft magazine was a full two pages. NostalgiaAir.com
has the more extensive Rider data pack. It had a very ornate wood laminate decor,
along with many 'extra' features found only in high-end radios of the day - such
as a Flash Tuner! More detail can be found on the RadioMuseum.org website...
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 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...
Withwave manufactures an extensive line
of metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated
4-port vector network analyzer (VNA) calibrator, between- and in-series connector
adaptors, attenuators, terminations, DC blocks, torque wrenches, test probes &
probe positioner. Special test fixtures for calibration and multicoax cable assemblies.
Frequency ranges from DC through 110 GHz. Please contact Withwave today to
see how they can help your project succeed.
Sunday the 26th
This custom RF Cafe
electronics-themed crossword puzzle for November 26th contains words and clues
which pertain exclusively to the subjects of electronics, science, physics, mechanics,
engineering, power distribution, astronomy, chemistry, etc. If you do see names
of people or places, they are intimately related to the aforementioned areas of
study. Being that "Z" is the 26th letter of the alphabet, it is used as the first
and/or last letter of many words in today's crossword puzzle - as well as in-between.
Those clues are marked with an asterisk (*). As always, you will find no references
to numbnut movie stars or fashion designers. Need more crossword RF Cafe puzzles?
A list at the bottom of the page links to hundreds of them dating back to the year
2000. Enjoy...
One aspect of advertising on the RF Cafe
website I have not covered is using
Google AdSense.
The reason is that I never took the time to explore how - or even whether it is
possible - to target a specific website for displaying your banner ads. A couple
display opportunities have always been provided for Google Ads to display, but the
vast majority of advertising on RF Cafe is done via private advertisers. That is,
companies deal with me directly and I handle inserting their banner ads into the
html page code that randomly selects and displays them. My advertising scheme is
what the industry refers to as a "Tenancy Campaign," whereby a flat price per month
is paid regardless of number of impressions or clicks. It is the simplest format
and has seemed to work well for many companies. With nearly 4 million pageviews
per year for RFCafe.com, the average impression rate per banner ad is about 280,000
per year (in eight locations on each page, with >17,000 pages). That's pretty
good exposure for $300 per month. Some companies have expressed an interest in being
able to manage their advertising accounts themselves a la the Google AdSense program...
The leading website for the PCB industry.
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 (FR-4, Rogers, flexible, rigid), Geographical
location (U.S., China), kinds of services (manufacturing, fabrication, assembly,
prototype), and more. Fast turn-around on quotations for PCB fabrication and assembly.
Friday the 24th
The demise of
Sears, Roebuck and Co. is very disappointing to me. As with many Americans (and
Canadians) of my era and prior, I grew up with Sears being literally (in the true
sense of the word, not the faux usage like "I literally thought I would die when
she told me...") a household name. We had Kenmore kitchen appliances (some, not
all), clothes irons and hair blowers, and of course Craftsman tools and a DieHard
battery in the family sedan, and some Toughskin clothes at the start of the school
year. We never, to my memory, had a Silvertone radio or record player. It's not
that the parents were Sears fanatics, just that our limited budget mandated buying
durable goods at a fair price. My own workshop is dominated by Craftsman tools,
many of which I have had for fifty years. Analysts say poor management and a failure
to embrace online sales were the primary causes for ultimate doom. This "A City
in a Store" article appearing in a 1937 issue of Popular Mechanics magazine
highlights the catalog sales business of Sears, along with the amazing conglomerate
of operations supporting both that and the brick and mortar retail sales locations.
Just as The Decline and Fall of the Roman Empire is a weighty, multi-volume tome
analyzing the human failings behind the tragedy, this Smithsonian magazine article
entitled The Rise and Fall of Sears assesses the Sears debacle. The conspiratorial
side of me suspects globalist true believers are directing and facilitating the
breaking down of Western stalwart institutions in order to erase history. The schools
nowadays do not teach the accomplishments and heroic parts of our past - only atrocities
like slavery and child labor. Flooding the country with aliens having no connection...
Significant advances in electronics - and
all other kinds of technology for that matter - occurred during World War II,
which in conjunction with the U.S. government selling surplus equipment at the end
of that war at very low prices, cause a boom in consumer electronics markets. The
established radio business and the fledgling television markets were abetted by
quickly expanding numbers of broadcast stations. This chart appearing in Radio-Craft
magazine from early 1948 show the number of currently licensed
AM, FM, and TV stations, with projections out 20 years to 1968. I don't have
the data from 1968, but almost certainly the numbers were much larger than predicted,
fueled largely by portable radios in automobiles and hand-carried models. Transistorized
circuits (the transistor was invented in 1947, just a month before this chart was
made) with their smaller size, smaller battery requirements, more rugged construction,
improved circuit designs, and higher reliability provided another major kick to
the market in the early-mid 1960s...
"Electronic transistors are central to modern
electronics. These devices precisely control the flow of electricity, but in doing
so, they generate heat. Now, researchers at the University of California, Los Angeles
have developed a solid-state
thermal transistor - the first device of its kind that can use an electric field
to control the flow of heat through electronics. Their study, which was recently
published in Science, demonstrates the capabilities of the new technology. 'There
has been a strong desire from engineers and scientists to control heat transfer
the same way we control electronics, but it has been very challenging,' says study
lead author Yongjie Hu, a professor of mechanical and aerospace engineering at UCLA.
Historically, electronics have been cooled down with heat sinks that passively draw
the excess heat away. More active approaches to thermal management have also been
proposed, but these often rely on moving parts or fluids and can take a long time
- typically minutes to hours..."
The name
Frank Conrad probably does not sound familiar to most people in the electronics
communications field today, but at one time he was the assistant chief engineer
to the Westinghouse Company. Back when voice radio (as opposed to Morse code, aka
CW) was being pioneered, Mr. Conrad was widely known for his efforts in commissioning
the country's first commercial broadcast installation - KDKA in Pittsburgh, Pennsylvania.
His arranging for live coverage of election night results in 1920 is credited for
launching a huge interest by consumers in purchasing radio sets for their homes
(Warren Harding beat James Cox that night, BTW). Toward the end of his career, Conrad
was active in helping develop television broadcast standards. Fortunately for us,
his electromechanical system gave way to a fully electronic system...
Empower RF Systems is the technological
leader in RF & microwave power amplifier solutions for EW, Radar, Satcom, Threat
Simulation, Communications, and Product Testing. Our air and liquid cooled amplifiers
incorporate the latest semiconductor and power combining technologies and with a
patented architecture we build the most sophisticated and flexible COTS system amplifiers
in the world. Solutions range from tens of watts to hundreds of kilowatts and includes
basic PA modules to scalable rack systems.
Thursday the 23rd
These "News
Briefs" features from Radio-Electronics magazine (c1967) are always
interesting. As has always been the case, some of the items predicting the future
of technology are either too wacky to ever be realized, or science has not yet advanced
far enough. Many - maybe most - products and concepts have advanced far beyond even
what the-present-day inventors imagined. This month's column is full of mostly the
latter types. A "lineless" (i.e., cordless) telephone (not cellphone) is demonstrated
by Bell Telephone Labs, with no mention of the frequency band. The "pocket television,"
presented by Sony, nowadays takes the form of a smartphone, and the programming
is received via an Internet connection rather than directly from local broadcast
towers. The "world's smallest detect," operating in the infrared was built on a
germanium substrate (maybe the bumble bee thought it was a geranium substrate?).
When I first saw RCA's giant UHF antenna, I thought it was the barrel of some sort
of cannon. Turns out those slots are not cooling ports but radiation ports...
Anatech Electronics 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. Three new
filters have been announced for November 2023: a 10 MHz LC bandpass filter
with BNC connectors with a bandwidth of 2.0 MHz, a 769-855 MHz cavity bandpass
filter with N-type connectors and a ripple of 0.2 dB maximum, and a 1000-2000 MHz
cavity bandpass filter with SMA connectors having a rejection of 20 dB minimum
at 2100 MHz. Custom RF power filter and directional couplers designs can be
designed and produced with required connector types when a standard cannot be found,
or the requirements are such that a custom approach is necessary...
Deciding which fuse to use as a replacement
for a blown fuse is usually a simple matter - read the part number or electrical
parameters (current, voltage) off the package and make sure of its type (fast or
slow blow). Of course whenever a fuse blows, you usually have more or a problem
than just a bad fuse.
Deciding which fuse to use when designing a circuit which requires overcurrent
protection requires a lot more consideration. This 1972 Popular Electronics
magazine article from fuse making company Bussmann's Charles James gives a brief
introduction to the kinds of parameters you need to factor into a selection. There's
more to it in most cases - especially for a shippable product - than measuring the
current under normal operating conditions and then adding some arbitrary buffer
like 20%. Extreme ambient temperature requires derating, mechanical conditions during
operation like high vibration or impact, time delay for more than a short-lived
transient event...
Anyone who watched the
WKRP in Cincinnati
sitcom back in the 1970s has to remember what was one of the funniest episodes ever.
Here is the 4 minutes that made Prime Time history. In this Thanksgiving episode,
station owner / manager Arthur Carlson decided he would surprise the community with
good deed - that doubled as a promotional stunt for his radio station - by dropping
turkeys from a helicopter for lucky shoppers at the local shopping mall. Watch the
disaster unfold as Les Nessman reports live, and then see Carlson's final comment
that is still used or alluded to in many comic routines. Posting this video is an
RF Cafe tradition. Have a Happy Thanksgiving!
Even in the early days of radio, some big-name
manufacturers built versions of their sets for the purpose of re-branding by another
company. Sears, Western Auto, Montgomery Ward, JC Penny, and others had the
own radio lines made by someone else. Here is an instance where three radios - at
least their electronics chassis - had identical (or nearly so) innards. As was common
at the time with AC/DC sets, one terminal of the
AC power line attached to the metal chassis as a common voltage reference, which
meant there was a 50-50 chance that the nonpolarized plug would be inserted into
the wall socket in a manner that connected the chassis to 120 VAC rather than
to ground (neutral). Everything on the outside was electrically isolated, by nonconductive
components (enclosure, knobs, switches), but many an unwitting radio owner got shocked
when attempting to service the set while it was plugged in (even if just removing
or inserting vacuum tubes). Designers eventually devised means of totally isolating
the metal parts - like installing a traffic light at an intersection after enough
people died in accidents there...
It was a lot of work, but I finally finished
a version of the "RF & Electronics Schematic & Block Diagram Symbols"" that
works well with Microsoft Office™ programs Word™, Excel™, and Power Point™. This
is an equivalent of the extensive set of amplifier, mixer, filter, switch, connector,
waveguide, digital, analog, antenna, and other commonly used symbols for system
block diagrams and schematics created for Visio™. Each of the 1,000 or so symbols
was exported individually from Visio in the EMF file format, then imported into
Word on a Drawing Canvas. The EMF format allows an image to be scaled up or down
without becoming pixelated, so all the shapes can be resized in a document and still
look good. The imported symbols can also be UnGrouped into their original constituent
parts for editing. Check them out!
Anatech Electronics (AEI) manufactures and
supplies RF and microwave filters for military and commercial communication
systems, providing standard LP, HP, BP, BS, notch, diplexer, and custom RF filters,
and RF products. Standard RF filter and cable assembly products are published in
our website database for ease of procurement. Custom RF filters designs are used
when a standard cannot be found, or the requirements dictate a custom approach for
your military and commercial communications needs. Sam Benzacar's monthly newsletters
address contemporary wireless subjects. Please visit Anatech today to see how they
can help your project succeed.
Wednesday the 22nd
I love a finely crafted gear as much as I
do a fancy vacuum tube. Worm gears are my favorite, maybe because they are what
I call the "diode" of gears. Due to their construction, applying a torque force
to the cylindrical worm gear transfers its rotation to the circular mating gear
(worm wheel); however, applying the torque to the worm wheel will not impart a torque
backward to the cylindrical worm gear. It's one-way action accommodates a force
transfer in just one direction, like a diode. There is no need for a lock or ratchet
to prevent the output from affecting the input. That is why tuning pegs on stringed
instruments use worm gears. It is why the drive gears on telescope axes use worm
gears. Winches use worm gears. One of the downsides of worm gears is that there
is no rolling force between surfaces - only a sliding force - so good lubrication
is essential to prevent excessive wear. This "ABC
of Gears and Gear Cutting" story from a 1944 issue of Popular Mechanics
magazine is a fairly in-depth dive into gear theory and manufacturing - and not
just for worm gears...
Regrettably,
I will not be renewing my membership with the American Radio Relay League (ARRL)
after it expires in March 2024. The ARRL recently announced that
dues will increase
from $49 to $59 per year (+20%) -- not unreasonable since they have remained the
same since 2016 (30%
inflation since then). However, that does not include the print version of
QST magazine anymore; you need to pony up another $25 for a hard copy.
Now, if the established value of print is $25 (let's use just $20), then the former
membership w/o print would have been only $(49-20) = $29. That makes the increase
for just membership a factor of two: (59/29=2) -- a 100% change!
Bidenomics has been steadily breaking my financial back, so costs need to be
trimmed; ARRL is a casualty. I'll miss sitting in bed reading QST and looking
for stories to reference here. In contrast, RF Cafe prices have remained steady
(advertising has decreased), so my effective income has gone way down in the past
three years. Nobody gives me a raise :-(
This might be one of the first advertisements
for
Rohde & Schwarz (R&S) test and measurement (T&M) products to appear
in a U.S. publication (December 13, 1965 Electronics magazine). A brief search for
earlier instances did not turn up anything prior to 1965. Please contact me if you
have seen one. R&S, as you probably know already, is now a major player in the
communications T&M world. Hewlett Packard (HP) of course was one of the largest
- if not the largest - maker of spectrum analyzers, network analyzers, noise figure
test sets, modulation generators and analyzers, signal generators, o-scopes, etc.,
up through about the 1980s - maybe into the 1990s. Once the cellular and wireless
everything markets took off, Rohde & Schwartz test equipment (TE) began appearing
on lab test benches more and more frequently. Engineers and technicians quickly
learned to appreciate the new advanced features that older industry stalwarts were
slow to adopt and incorporate. Then, in the early 2000s, HP decided to divest its
TE market into a new company with a weird, totally unfamiliar name (Agilent, now
weirdly named Keysight), leaving a lot of customers with strong brand loyalty feeling
abandoned (gotta admit I was one of them). The switch to other brands was made much
easier from then on, and, at least where I worked at the time, labs and production
test areas began mutating in color from gray to light blue. Since this was first
posted, a guy wrote to tell me he found a few pieces of brand new R&S test equipment
in the attic of an old house in Germany (none of the models in this ad). I put him
in touch with Rhode & Schwarz corporate to see whether they would be interested...
You might recall the April 2023 issue of
the ARRL's QST magazine featuring an article "The Better Antenna: Copper Versus
Aluminum." It was, as could be discerned when reading, written for Fools. Jose Luis
Giordano decided to use the occasion to write a "real" article explaining the pros
and cons of copper and aluminum. "The
Best Metal for an Antenna" appears in the December 2023 issue of QST. He includes
data and calculations for wire sag as a function of weight, length, and tensile
strength (resistance to stretching). He mentions the curve formed under the influence
of gravity being called a "catenary." I remember learning in math class that its
mathematical function is the hyperbolic cosine (cosh), and that
catenary stems from the Greek
word meaning "chain," from how a chain, cable, or rope sags. Someone posted a scan
of the full article on the Radio Club of Chile website. For some reason, ARRL does
not make the contents of QST available to non-members...
The following announcement was posted in
the September 1930 edition of Radio-Craft magazine regarding Radio Data Service
Sheets: "We are pleased to announce that RADIO-CRAFT has taken over the subscription
list of 'RADIO SERVICE,' formerly published in Dallas, Texas. All subscribers of
record to RADIO SERVICE will receive RADIO-CRAFT until the expiration of their subscriptions."
Prior to that, the "Radio Service" company must have contracted with Radio-Craft
to provide the information. This one in particular features the
Fada Radio and Electric Company of Long Island, New York, models 265-A and 475-A.
Thanks to the nomenclature plate on the "7" listed on eBay, we see that FADA stands
for F.A.D. Andrea, Inc. We still don't know what the initials stand for, though.
I had the Wayback Machine™ capture a copy of the listing so that the photos
will be available in perpetuity. A magazine ad for the FADA "Special" on the RadioMuseum
website shows a price of $95, which in 2023 money is the equivalent of $1,709 -
yow!
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...
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. 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 - and don't miss the blog articles!
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
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