See Page 1 |
2 |
3 |
4 | of the March 2023 homepage archives.
Friday the 31st
OTA Superception
It is no secret that I consider Hugo Gernsback to have been one of the last century's
premier technology innovators, futurists, and publishers. Many of his proposals,
prognostications, predictions, forecasts, and maybe even prophecies came to fruition
in his lifetime - often due to his own efforts. In the case of the
burgeoning wireless entertainment industry (radio and television), Gernsback
commented on the contention between household members over which program should
be tuned in. To wit from a 1960 issue of Radio-Electronics magazine: "Yes,
a family may conceivably have two separate radios and three TV sets, each in a different
room - everyone has seen such split households - but we must all agree that this
is an asinine and not very progressive solution to the problem, even if sufficient
rooms are available. It won't prevail in the future." This didn't really happen
until the availability of smartphones and wideband streaming video, so sometime
around 2008 - about six decades later...
IC Helps Mobile Devices Block Interference
"Researchers at MIT, Massachusetts have
developed a circuit architecture that targets and
blocks unwanted signals at a receiver's input without hurting its performance.
They borrowed a technique from digital signal processing and used a few tricks that
enable it to work effectively in a radio frequency system across a wide frequency
range. This innovation is especially relevant for crowded settings. Imagine sitting
in a packed stadium for a pivotal football game - tens of thousands of people are
using mobile phones at the same time, perhaps video chatting with friends or posting
photos on social media. The radio frequency signals being sent and received by all
these devices could cause interference, which slows device performance and drains
batteries. MIT's receiver blocked even high-power unwanted signals without introducing
more noise, or inaccuracies, into the signal processing operations. The chip, which
performed about 40 times better than other wideband receivers at blocking a special
type of interference, does not require any additional hardware or circuitry..."
The Transistom
The story from a 1958 issue of Radio-Electronics
magazine documents development of the "transistom"
device back in the 1958 timeframe. Keep in mind that it was just a decade earlier
that Mssrs. Bardeen, Brattain, and Shockley introduced the transistor amplifier
to the world. The transistom was basically a 3-terminal transistor with two additional
leads for a revolutionary power source built from radioisotopes of magnesium and
manganese. In the day, school kids, including me, were handed blobs of liquid mercury
to inspect and pass around in class, demonstrating how relatively ignorant we were
about things we now consider to be extreme health hazards. Accordingly, encapsulating
radioactive material in consumer devices was not a concern. The complete absence
of transistoms in the marketplace today speaks volumes about its success. Then again,
the month of publication of this article, and its author, might have something to
do with it...
Black Hole Mass Ejection Approaching Earth Orbit
At 04:23 UTC, a consortium of astronomers
using the Even Horizon Telescope (EHT) reported confirmation of the presence of
a massive cluster of
highly energetic deep space particles heading toward Earth orbit. It is believed
based on a time sequence of measurements over the past 12 hours that the mass originated
in the area of a supermassive black hole in the M87 galaxy (Messier object), approximately
54 light years distant. Currently crossing inside the extreme outer boundary of
the Kuiper Belt region, measurements have determined there is a very strong concentration
of energy in the 1.225 GHz (1225 MHz) and 2.428 GHz (2428 MHz)
electromagnetic spectrum. While the nature of such particle clusters generally consists
of a wideband dispersion of frequencies, these two wavelengths are of great concern
because 1.225 GHz is very close to the 1.2276 GHz (1227.6 MHz) "L2"
signal which is a critical component of the Global Positioning System (GPS) navigation
signal, and 2.428 GHz falls within the 2.4 through 2.5 GHz Industrial,
Scientific, and Medical (ISM) band used worldwide for unlicensed wireless communications.
Highly accurate measurements have not been made yet of the exact trajectory or energy
levels worst case scenario since the antenna array's pointing capability has been
exceeded as the result of the Earth turning away from the source. Approximately
eight more hours will be needed to re-acquire the signal...
Contra-Polar Energy
Contra-polar (negative) energy is a concept
that has been investigated by many researchers beginning in the mid 19th century,
when the nature of energy was beginning to be understood from a truly scientific
perspective. Entire theories of universe and matter-antimatter creation have been
published, reviewed and refined. This article from the April 1955 edition of
Popular Electronics magazine reports on then-current applications of contra-polar
energy. At the time, most such work was performed in secret government laboratories
and at test ranges that were closed to the public and results banned from publication,
but since that time freedom-of-information-act requests have opened much contra-energy
research information for public access...
Post Your Engineer & Technician
Job Openings on RF Cafe for Free
/jobs.htm">RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable /jobs.htm">job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
quality visitors...
Many Thanks to Reactel for Their
Long-Time Support!
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
Thursday the 30th
New Radiation Standards Set
Governments are historically fond of creating
laws, standards, regulations, codes, ordinances, directives, notices, prohibitions,
restrictions, bylaws, ordinances, and all other manner of ways to control our lives
- all for our own good, don't you know. Sometimes those impositions are useful,
and other times - maybe most times - they are just forms of control to keep the
figurative boot on the equally figurative throats of the proletariat. According
to this 1969 issue of Radio-Electronics magazine, the U.S. Department of
Health, Education, and Welfare has recently been ordered to create
standards for maximum radio frequency radiation exposure levels for various
commercial electronic products. The move was largely driven by concerns over radiation
from color televisions x-ray emission from super high voltage cathode ray tube (CRT)
biases, and from microwave ovens, both of which were relatively new household appliances...
Time Reflection Measured in Microwaves
"Physicists in the U.S. have observed an
effect known as
time reflection in an electromagnetic wave for the first time. They detected
the phenomenon - the temporal counterpart of familiar spatial reflection - by rapidly
switching a series of capacitors in a novel type of metamaterial. They say the result
could improve wireless communication and ultimately help bring about long-sought-after
optical computing. Everyday reflection involves the transformation of a wave packet
when it meets an interface in a distinct region of space. The process preserves
temporal ordering, so that the leading part of the incident wave remains ahead after
reflection. This means that objects further from a mirror look more distant in the
reflection, while sounds in an echo arrive back in the same order they were emitted.
Time reflection instead involves a wave packet being transformed as a result of
an abrupt change in time that applies equally throughout the medium it is traversing.
In other words, the material in question experiences a sudden shift in its properties..."
Mac's Radio Service Shop: Advertising for Dessert
Return on investment for advertising is
always a prime consideration for companies, regardless of how wide the perspective
audience or the size of the competition. Luck plays some part in whether a certain
advertising campaign is successful, but as Mac points out in the July 1949 edition
of Radio & Television News magazine, there is great advantage to
measuring the effectiveness of each advertising strategy. Advertising has never
been cheap, especially in venues with a large contingent of followers. In the Internet
age, one of the more popular schemes is 3rd-party pay-per-click ads that are served
by a central distributor (like Google and Bing) based on intelligent algorithms
designed by teams of business and marketing experts. Based on my conversations with
some RF Cafe advertisers who have tried Google's AdWords program, most are not happy
with the results because they experience a low ratio of clicks-to-sales. Those who
report success are people who have expended a lot of effort learning how the system
works and how to exploit it - often after learning the hard way what the wrong way
is. Unlike his fellow radio service and sales shops operators in the story, it is
doubtful many businesses would be willing to share their hard-earned secrets with
competitors...
You Don't See This Every Day!
Whilst on the way to a doctor appointment this morning (3/30/2023), we saw this
guy driving his car with the
hood smashed into
the windshield. It appears the wind stream must have blown it back while driving
down the road since the windshield was smashed as well. We followed him for about
5 miles on West Wendover Road, in Greensboro, NC, before he turned off onto a side
road. How he managed to see well enough to guide the car is a mystery. There must
have been a slim line of sight between the dashboard and under the edge of the hood
based on how he was leaning over in the seat. Other drivers kept well away from
him, but I had to take a risk and get up next to him to get this video. It was extremely
dangerous of him to do so, but awfully funny as well.
Teledyne Relays 50+ GHz
Mini Matrix Boxes
Teledyne Relays, a leading provider of high-performance
coaxial switches, is pleased to announce the addition of 50+ GHz
coaxial switches to its
Mini Matrix Box product line. The new switches are available in SPDT, Transfer,
and Multi-throw configurations each with their own GUI. They can be ordered with
or without terminations, offering flexibility for various applications in RF and
automated test equipment. Teledyne Relays Mini Matrix Boxes are a compact, plug-and-play
solution, offering USB or Ethernet control for efficient and reliable switching
in laboratory and production environments. With the addition of the 50+ GHz
switches, Teledyne Relays can meet the growing demand for testing higher frequency
applications in the industry. "The introduction of the 50+ GHz coaxial
switches is an exciting milestone for Teledyne Relays. We are committed to delivering
high-quality, reliable, and innovative solutions that help our customers stay ahead
of the curve," said Michael Palakian, Teledyne Relays Vice President of Global Sales &
Marketing...
Color Television?
The 1954 Tournament of Roses (aka Rose Bowl
Parade) was famously the
world's first national commercial color television broadcast, provided by the
National Broadcasting Company (NBC). Prior to the NTSC (National Television Systems
Committee) finally settling on an all-electronic scheme for TV sets, many electro-mechanical
and electro-optical types were developed. The integrated RGB (red, green, blue)
color gun within a cathode ray tube (CRT) was a relatively new concept in 1949.
This Radio & Television News magazine article presents some of the
propositions by the two major research and development players at the time: RCA
and CBS. They might seem ridiculous in the light of knowledge available now, but
a round wheel wasn't immediately obvious to Oog sitting in his cave, trying to figure
out an easier way to transport that mastodon carcass...
RF Cascade Workbook
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...
Many Thanks to Aegis Power Systems for
Their Continued Support!
Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today. Manufactured in the USA.
Wednesday the 29th
News Briefs: e-Vehicles & More
Hugo Gernsback was the Ulrich L. Rhode
of the early 20th century; he was very accomplished in many areas of electronics,
was a prolific publisher of technical content, knew everyone of any import in the
technology realm, had successful business ventures, and seemed to always be getting
presented with awards from one group or another. With guys like Gernsback and Rhode,
organizations considered themselves honored to have their offers accepted in order
to be worthy of the recipient's attention. This collection of industry New Briefs
in the January 1967 issue of Radio-Electronics magazine included the Antique Wireless
Association (still in existence) giving an award to Gernsback. It also reported
on General Motors using silver-zinc battery packs, SCR's and specially designed
ac motors in its experimental Electrovair II - a conversion of its gas-powered Corvair.
The government-controlled BBC's domination over "free" radio broadcasting was getting
a challenge from the Popular Music Authority (PMA), which was also a government-controlled
broadcaster (nothing Soviet about that arrangement, eh?). Increasing sun spot activity
opened up the 11-meter shortwave band...
Microsatellites Reduce Space Junk
"Satellite powered by 48 AA batteries and
a $20 microprocessor shows a low-cost way to
reduce space junk. Common sense suggests that space missions can only happen
with multimillion-dollar budgets, materials built to withstand the unforgiving conditions
beyond Earth's atmosphere, and as a result of work done by highly trained specialists.
But a team of engineering students from Brown University has turned that assumption
on its head. They built a satellite on a shoestring budget and using off-the-shelf
supplies available at most hardware stores. They even sent the satellite - which
is powered by 48 Energizer AA batteries and a $20 microprocessor popular with robot
hobbyists - into space about 10 months ago, hitching a ride on Elon Musk's SpaceX
rocket..."
Bell Telephone Labs Coaxial Cable
When you read today where someone writes
about, "back in the eighties...," you naturally think of 1980-something. This 1949
Radio & Television News magazine advertisement from by Bell Telephone
Laboratories mention of "back in the eighties" was referencing the 1880s, not the
1980s. What was six decades ago at the time is now thirteen decades ago - yikes!
The picture juxtaposes a telephone pole massively populated with horizontal cross
timbers, insulators, and wires, with an engineer holding up a section of coaxial
cable that was in the process of replacing the poles and wires. Thanks to Bell Labs'
relentless R&D efforts, those early single-channel,
short distance twisted pairs were obsoleted by 1,800-channel coax. Fiber optic
cables today typically support more than 30,000 voice channels...
Measuring with Humor
A relatively new feature has been appearing
on the Microwaves & RF website entitled "Measuring
with Humor," compliments of Fluke Calibration. I just saw it and don't know
how long it has been running, but there are four of them thus far. The comic depicts
situations commonly experienced by people in the test equipment realm. Fluke, of
course, is one of America's most well-known and oldest test equipment manufacturers.
I have used
Fluke (founded in 1948) gear since first entering the electronic and electrical
field in the 1970s. It always seemed strange to me that a high end electronic test
equipment company would assume the name "Fluke," even though it is the name of company
founder John Fluke. Even though a fluke can be defined as an unexpected stroke of
good luck, it often has a negative connotation describing an outlier event not typical
of the norm. The Fluke company's good reputation is due to smart employees who design
and manufacture good products - definitely not a fluke.
Understanding the JFET
Adolph Mangieri, who authored articles in
other electronic magazines in the 1970s and 1980s, provides a good introduction
to
junction field effect transistors (JFETs) in this 1973 piece in Popular
Electronics magazine. As mentioned, JFETs were a relative newcomer at the time
to the commercial electronics world because of high fabrication costs. Obtaining
consistent pinch-off voltages and gains was largely responsible for the relatively
high production costs due to substrate purity and doping issues. Semiconductor processing
and some circuit application examples are included. One of the first big commercial
applications of the JFET was probably transistorized multimeters, which enabled
a very high input impedance. Doing so helped minimize the loading effect on the
meter on the circuit under test...
Post Your Engineer & Technician
Job Openings on RF Cafe for Free
/jobs.htm">RF
Cafe's raison d'être is and always has been to provide useful, quality content for
engineers, technicians, engineering managers, students, and hobbyists. Part of that
mission is offering to post applicable /jobs.htm">job openings. HR department employees and/or managers of hiring
companies are welcome to submit opportunities for posting at no charge. 3rd party
recruiters and temp agencies are not included so as to assure a high quality of
listings. Please read through the easy procedure to benefit from RF Cafe's high
quality visitors...
Many Thanks to ConductRF for Continued
Support!
ConductRF is continually innovating and
developing new and improved solutions for RF Interconnect needs. See the latest
TESTeCON RF Test
Cables for labs. ConductRF makes production and test coax cable assemblies for
amplitude and phased matched VNA applications as well as standard & precision
RF connectors. Over 1,000 solutions for low PIM in-building to choose from in the
iBwave component library. They also provide custom coax solutions for applications
where some standard just won't do. A partnership with Newark assures fast, reliable
access. Please visit ConductRF today to see how they can help your project!
Tuesday the 28th
Electronics-Themed Comics
It's Monday again. Here is another batch
of
electronics-themed comics to help cheer you up. They appeared in the April 1963
issue of Radio-Electronics magazine. Usually the meaning of the comics
is immediately apparent, or maybe after a little critical investigation, but I'm
going to need some help with the page 20 comic. I must be missing something obvious.
There is nothing else on the page it came from that it is supposed to go with. Maybe
it is simply implying the lonely life of a TV repairman on a service call. The page
49 comic plays on the era's popular notion of a husband-wife battle involving his
quest for bigger and better (and more expensive) electronics gear. If you don't
"get" the humor, note the stacking of the equipment - which is stereo. Page 88's
topic is as apt today as it was 60 years ago. Page 105 is yet another instance of
man's obsession with stereos back in the day...
IDTechEx Report on 6G Market 2023-2043
"IDTechEx, an independent market research
and business intelligence provider claims that 6G will arrive in 2028 at the earliest
in its recently published market research report, "6G
Market 2023-2043: Technology, Trends, Forecasts, Players". 6G, compared to its
predecessor, is expected to offer significantly better communication capabilities,
such as Tbps-level peak data rates, microsecond-level latency, and 99.99999% network
dependability. Although 6G promises a lot, it is unlikely that 6G will be in daily
life soon, despite the fact that several important companies and nations have already
begun 6G research, as shown in the figure below, the telecom industry needs to address
several issues before seeing the success of 6G. The difficulties are not only in
THz technology but also in identifying applications that will fuel 6G adoption.
IDTechEx has been researching 5G and 6G for years. This article will discuss some
of the hardware-related hurdles to 6G connectivity..."
Barry Goldwater, K7UGA, Ham Radio Operator
A lot of famous people have been or are
currently
amateur
radio operators, including many present-day astronauts who broadcast from the
International Space Station (ISS). Some media people, like Tim Allen, star of the
Home Improvement and Last Man Standing fame, became a Ham after
playing a character who is one on his show. A 1958 edition of Popular Electronics
magazine published a story titled "VIP's Are Hams Too!," which included Arthur Godfrey
(9K4LIB), Herbert Hoover, Jr. (W6ZH), and Arthur Collins (W0CXX). I wrote an article
on radio host Jean Shepherd (K2ORS), of "A Christmas Story" fame. Senator Barry
Goldwater (K7UGA), of Arizona, was also an active Ham, as evidenced here in this
May 1967 edition of the ARRL's QST magazine. Senator Goldwater also appeared
in the June 1967 issue of QST...
EMI in Connected Vehicles
"Automakers
need to rein in
electromagnetic interference before it pumps the brakes on in-vehicle connectivity
innovations. In early 1979, Ralph Liuzzi installed a mobile transmitter in his customer's
Cadillac Seville. However, Mr. Liuzzi found that whenever he attempted to transmit,
the car's engine would stall, resulting in a serious safety hazard for both driver
and pedestrians. At the time, the National Highway Traffic Safety Administration
(NHTSA) cited a 'lack of documentation on the effects of Electromagnetic Interference
(EMI) on automobile electronic engine control systems,' but reviewed the case and
eventually found that indeed EMI played a key role in the system malfunction. 'The
problem of EMI is a relatively new one in automotive technology since electronics
have only recently been introduced into usage in automobiles,' the NHTSA said in
its report. Now, more than 40 years later, the problem of EMI has only grown..."
Hetro Air-Ace Series M, 4-Band Superhet
This is another Radio Service Data Sheet
which appeared in the May 1936 edition of Radio-Craft magazine. I post
this schematic and functional description of the
Hetro Air-Ace Series M, 9-Tube 4-Band Superhet manufacturers' publications for
the benefit of hobbyists and archivists who might be searching for such information
either in a effort to restore a radio to working condition, or to collect archival
information. A thorough search on the Internet turned up no examples of a surviving
instance of the Hetro Air-Ace Series M radio. BTW, the "Air Ace" part of the
name refers to the radio air, as in "on the air" or "over the air," not a fighter
pilot ace with a certain number of kills painted on the side of his airplane...
Promote Your Company on RF Cafe
New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website 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. 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.
Many Thanks to Berkeley Nucleonics
for Continued Support!
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.
Monday the 27th
Electronics Mathematics Quiz
Don't let the title scare you away from
this "Electronic
Mathematic Quiz." It appeared in the June 1969 issue of Popular Electronics
magazine, and was created by quizmaster Robert Balin. There are no scary equations
to complete and no mental calculations to bend your brain. Instead, the "mathematics"
required is to recognize physical and electrical signal shapes which are described
by common mathematics terms. For instance, a cardioid approximates the electromagnetic
radiation pattern of many directional antennas, which may include a parabolic dish.
Differentiator and integrator circuits generate distinct waveforms. Phase angles
and critical angles are familiar to circuit designers and radio operators. Shape
letter "E" will likely be familiar according to its name, although you might not
know what it is in the world of electronics...
Ultrathin Metasurface Display Rivals LCD
"Currently, LCD screens are the most dominant
and popular display technology for televisions and monitors, but they are unlikely
to get significantly better in the future. Now a new study finds the kind of physics
that make microscopic 'invisibility
cloaks' possible may lead to next-generation 'metasurface' displays roughly
1/100 the thickness of the average human hair that could offer 10 times the resolution
and consume half as much energy as LCD screens. LCD technology depends on liquid
crystal cells that are constantly lit by a backlight. Polarizers in front and behind
the pixels filter light waves based on their polarity, or the direction in which
they vibrate, and the liquid crystal cells can rotate the way these filters are
oriented to switch light transmissions on and off. LCD screens do continue to see
advances by improving the liquid crystals, the display technology or the backlight.
'However, improvement on LCD technologies are now mostly just..."
Howard Explorer Model W All-Wave Superhet
Here are the schematics, chassis layout,
and service info for the
Howard Explorer Model W Deluxe 19 Tube All-Wave Superheterodyne console
style (sits on the floor) radio. The wooden cabinet format is somewhat unusual in
that the top is a flat surface rather than the having more typical curvaceous lines
that radios of the era sported. It looks a lot like the models with built-in phonographs,
where the top would tilt upward. The Radio Service Data Sheets that were published
in Radio-Craft usually seem to have more information included than those published
in other magazines, at least in the same era (1940-ish). It might have to do with
how much material is provided by the manufacturer rather than a decision by the
magazine editors. This one appeared in the September 1934 issue. Believe it or not,
there are still people searching for such data. I could not find an example of a
real surviving Howard Explorer Model W radio...
Morse Code Rhythm Patterns from A to Z
Given that this "Morse
Code Rhythm Patterns from A to Z" article (p58) appeared in the April issue
of QST magazine, I was careful to ascertain that it was not written for
fools. It seems authentic, but for the life of me I don't know how many people would
find the proposed Morse Code learning system to be a natural method. Author Bill
Cody (K3CDY) is a musician who is accustomed to reading music, so for him and other
talented musical types, maybe such a system facilitates the learning of code. To
people like me, it's like suggesting a method for more easily learning how to apply
a bandage by adapting brain surgery principles. Unfortunately, you'll need to be
an ARRL member for access to the online article, or maybe you can borrow a copy
of the magazine from a friend (but you'll still need to sign in for the music/code
sheets). I'm still trying to figure out which article is the April Fools bait. BTW,
I remember using one of those Isolate Pad Circuit-Board Construction tools when
making proto boards (p91).
Micro-Waves Span the English Channel
We "Baby Boomers" remember a time when cell
towers did not present a ubiquitous (and, frankly, ugly) presence across the landscape.
Microwave relay towers for television and telephone links could be spotted sitting
atop hilltops and mountain ridges in some areas, and giant television and radio
station towers sat behind broadcast stations, and multi-element antennas dotted
house rooftops everywhere. Our grandparents (Millennials' great grandparents) remember
when even microwave relay towers were missing. This 1936 article reports on the
first microwave links spanning the English Channel to replace expensive and trouble-prone
submerged cable. Part of the impetus, not mentioned within, was the building inevitability
of war with Germany and the vulnerability of those communications links to being
compromised by Nazi submarines and divers...
RF Cascade Workbook
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...
Many Thanks to Exodus
Advanced Communications for Their Support
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.
Sunday the 26th
Electronics Theme Crossword for March 26th
This custom RF Cafe
electronics-themed crossword puzzle for March 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. 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.
Many Thanks to Withwave for Long-Time Support!
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.
Friday the 24th
Electronic Video Recording | Color TV
In the pre-VHS era, companies were vying
to create and set standards for the
home-based video recording and playback industry. The same sort of scenario
played out over color television standards a decade earlier, and over B&W television
a couple decades before that. Such battles for dominance in emerging technologies
were not new, and continue into the current time. Various schemes for Electronic
Video Recording systems were being used by commercial media, but creating devices
affordable to Harry and Harriet Homeowner was a challenge. Betamax, produced by
Sony, hit the store shelves in 1975, then VHS a year later. A sort of 8-track vs.
compact cassette battle ensued, but VHS clearly emerged as the winner - followed
by DVD and Blu-ray. Also reported was the world's most expensive - and feature-filled
- color TV, built by Philips, that was "more computer than television," being able
to operate on eleven different modulation standards...
Carbon Nanotube Wiring on Plastic Films
"Researchers at Tokyo University of Science
have proposed a novel method to fabricate
multi-walled carbon nanotube (MWNT) wiring on a plastic film under ambient conditions
using a low-cost laser. The properties of Carbon nanotubes (CNTs) include high strength,
low weight, and excellent thermal and electrical conductivities. This makes them
suitable materials for applications including reinforcement materials, energy storage
and conversion devices, and electronics. Despite their potential, it has proven
challenging to incorporate them onto plastic substrates for fabricating flexible
CNT-based devices. The breakthrough from Japan involves coating a polypropylene
(PP) film with an MWNT film about 10μm thick and then exposing it to a mW UV laser.
The result is a conductive wiring made of a combination of MWNT and PP. The research
is detailed in Scientific Reports. This process enables the easy 'drawing' of wiring
and flexible devices for wearable sensors without the need for complex processes..."
Belmont Model 5D128 Tabletop Radio
The
Belmont model 5D128 was a compact, inexpensive tabletop AM radio set. A schematic
and parts list for it appeared in the November 1946 issue of Radio News
magazine. There are still many people who restore and service these vintage radios,
and often it can be difficult or impossible to find schematics and/or tuning information,
so I scan and post them whenever they appear in magazines which I own. While researching
the Belmont 5D128 tabletop radio, I ran across an excellent video created by Mr. Paul
Carson, as part of his Mr. Carlson's Lab series (note how the setting looks like
he's in the ISS). Here is a great video of Mr. Carlson troubleshooting an intermittent
noise problem in a receiver. That "Carlson RF SuperProbe" he is using looks like
a must-have piece of test equipment The Belmont 5D128 was rebranded by other companies
such as Airline, Coronado, Lafayette...
IPP-5014, 30-1000 MHz
Transformer
Innovative Power Products (IPP), with more
than 30 years of experience designing & manufacturing RF & microwave passive
components, Innovative Power Products introduces our model IPP-5014, a 100 watt
surface mount
single-ended transformer that operates from 30 to 1000 MHz. The IPP-5014
is a single-ended impedance transformer that operates from 30 to 1000 MHz with
a 4:1 transformation ratio and 100 watt average power rating. The IPP-5014
transforms impedance from 50 ohms at J1 to 12.5 ohms at J2. The insertion loss
is less than 0.75 dB from 30-50 MHz and less than 0.60 dB from 50-1000 MHz.
The VSWR is less than 1.43:1. Single-Ended Transformers are used to match devices
of differing impedances. Innovative Power Products can also customize our single-ended
transformers to fit your project...
National Company: TMS Condensers
National Company, an early manufacturer
of electronics components for radio products, ran a series of unique advertisements
in the ARRL's QST magazine. Rather than using precious cash for directly
promoting specific products or product lines, company president John Millen occupied
full pages with text explaining why it makes the things it does and how they can
be used to solve problems or enhance performance. This article/ad on TMS condensers
(aka variable capacitors) was number 61 in the series, which means if they printed
one every preceding month, the first would have appeared in the March 1934 issue
of QST...
RF & Electronics
Symbols for Visio
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...
Many Thanks to Amplifier Solutions
Corporation (ASC) for Continuing Support!
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.
Thursday the 23rd
Electronics News Briefs
Lots of interesting topics were reported
in
News Briefs from the April 1960 issue of Radio-Electronics magazine.
One that is relevant even today is the assigning of new numeric prefixes tera for
a trillion; giga for a billion; nano for a billionth, and pica for a trillionth.
If you have read vintage science and engineering publications, you know that, for
instance, what is now called pica (a la pF, 10-12) used to be written
as micromicro (a la μμF, 10-6x10-6 = 10-12). Here
is an example of μμF being used. Less commonly seen was something like millimicroamperes,
which is 10-3x10-6 = 10-9, now known as a nanoamperes,
nA. A new television picture tube which used a solid state electron emitter in place
of a heated cathode was announced for portable TVs, potentially doubling battery
life. Did you know that in 1960, the South African government felt that TV would
be detrimental to children and "the less developed races," thereby justifying its
anti-TV policies? Following on the results of the International Geophysical Year
(IGY) discoveries, atmospheric ducts for radio signal transmission propagation were
being found worldwide...
Accurate Multi-Channel Radar Signal Generation
Engineers at Berkeley Nucleonics Corporation
(BNC) and AnaPico teamed up to write a paper entitled "Phase
and Timing-Accurate Multi-Channel Radar Signal Generation." It begins: "Engineers
testing radar require the ability to generate multi-pulse streams with each pulse
supporting dozens of parameters such as frequency, amplitude, phase, pulse width,
time position and intrapulse modulation or chirping. Table 1 summarizes the typical
parameter set describing a single radar pulse, known as a pulse descriptor word
(PDW). A list of PDWs will fully describe a radar pulse stream. Multi-patch radar
antenna arrays require additional parameters for full characterization. For these
arrays, inter-channel phase coherence, which addresses relative phase stability
becomes important. Phase-coherent switching, where the relative phase between channels
is stored in memory and inter-channel timing accuracy are also critical parameters..."
A version of this article also appears on the
MWJ website.
General Electric Germanium Transistors
"If you're not using transistors already,
chances are you'll consider them for amplifiers and oscillators in future circuits."
So says the line in an advertisement for General Electric
vacuum-sealed
transistors in a 1953 edition of QST magazine. To say the claim was
prescient is an understatement. A lot of people resisted the switch to transistors
for many years - especially hobbyists who had grown accustomed to working with vacuum
tubes. Maybe GE figured pitching the newfangled devices as being "vacuum-sealed"
would help the hardliners soften their opposition to them. Not mentioned in the
ad is that these three transistors - the 2N43, 2N44, and 2N45 - are all germanium-based.
It wasn't until May of 1954 that Texas Instruments (TI) announced the commercial
availability of grown-junction silicon transistors...
Pulse Fidelity for High-Power GaN Radar and EW Tx's
Microwave Journal magazine has
a useful article posted entitled, "Innovations
in Pulse Fidelity for High-Power GaN Radar and EW Transmitters." Darren Miles
and George Bollendorf, of Empower RF Systems and Bob Buxton, of Boonton Electronics
team up to present a method for accurately measuring and compensating distortions
in pulses driving the output stage. It begins: "Radar and electronic warfare (EW)
have been the primary applications for extremely high-power transmitters, driving
the demand for specialized high-power traveling wave tubes (TWTs) and magnetrons.
Diminishing sources of TWT supplies, coupled with their poor reliability, inefficiency,
large size and high total lifetime cost of ownership are causing a migration away
from tubes. While improved pulse fidelity accompanies the shift to solid-state transmitters,
next-generation radar depends on further improvements in waveform fidelity and flexibility.
Next-generation radar systems utilize long pulse widths, which present specific
challenges. In response, Empower RF Systems has developed technology to reduce pulse
distortion as a development step towards pulse shape matching, allowing the reproduction
of the input pulse without distortion. The pulse correction is performed within
the amplifier in real-time. This is important because long pulse width radar is
especially vulnerable to over/undershoot and droop...
When Your Phone Is Spying on You
"Smartphone spyware apps
that allow people to spy on each other are not only hard to notice and detect, they
also will easily leak the sensitive personal information they collect, says a team
of computer scientists from New York and San Diego. While publicly marketed as tools
to monitor underage children and employees using their employer's equipment, spyware
apps are also frequently used by abusers to covertly spy on a spouse or a partner.
These apps require little to no technical expertise from the abusers; offer detailed
installation instructions; and only need temporary access to a victim's device.
After installation, they covertly record the victim's device activities - including
any text messages, emails, photos, or voice calls - and allow abusers to remotely
review..."
Galvin Motorola Model 61 Automotive Receiver
What the heck is an
Elkonode? That was my response to its mention in this Radio Service Data Sheet
for the
Galvin Motorola Model 61 Automotive Receiver. The Mallory-Elkon Elkonode was
an electromechanical vibrator device for DC-DC conversion. An oscillating circuit
opened and closed a set of contacts being fed with the automobile's DC supply, thereby
creating a chopped waveform which was applied to a step-up transformer, then rectified
and filtered to provide the high plate voltage for the radio's vacuum tubes. A Google
search turned up a datasheet on the Mallory Elkonode. Per the info, "The series
60, 70, and 80 Mallory Elkonodes are described as single-reed, full-wave inverters,
with self-contained synchronous rectifiers. These units within themselves supply
direct current, high voltage for radio receiver plate supply. No tube rectifiers
are required with these types." This 1932 Radio-Craft magazine article
recommends against attempting self-repair of Elkonodes (aka interrupters), so restoration
buffs will appreciate the instructions offered in the datasheet...
RF & Electronics Symbols
for Office™
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!
Thanks to PCB Directory for Continued
Support!
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.
Wednesday the 22nd
What Happened at Oslo? Color TV
It is kind of hard to believe that even
by 1966, when the International Telecommunications Union (ITU) met in Oslo, Norway,
that the world had not yet agreed in a common
transmission standard for color television. In January of 1967, Radio-Electronics
magazine editor Thomas Hasket interviewed two major players in the industry, George
Brown of Radio Corporation of America (RCA), and Frederick M. Remley, Jr. of Society
of Motion Picture and Television Engineers (SMPTE), regarding the stalemate that
was unarguably hampering the ramping up of color television set production. Consumers
were pining for them, but companies hesitated to invest engineering and manufacturing
resources when they couldn't be sure it would not be thwarted by a change in the
modulation scheme. A battle was being waged between the U.S. NTSC standard and the
European PAL system (and SÉCAM to a lesser sense). Both had strengths and weaknesses,
but history has shown, NTSC ultimately won. Possibly due to the impasse, color TV
sales in America did not surpass B&W sales until the early 1970s...
Anatech Electronics March 2023
Newsletter
Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his March 2023 newsletter that features
his short op-ed entitled "Healthcare
Industry IoT Security Under Threat," which discusses some of the issues compromising
not just healthcare privacy, but the whole Internet of Things (IoT) effort. The
fact is your healthcare records have been anything but secure and private for a
long time. The Health Insurance Portability and Accountability Act of 1996 (HIPAA),
which is responsible for the glass or Plexiglas barriers with the small transaction
opening installed at the reception desks at doctor and dentist offices, was supposed
to make people feel that their medical history was being protected against prying
eyes, physically and digitally. That has been as effective as requiring everyone
to wear a cloth facemask to protect them against a virus. My guess is that nearly
every form of personal information is available on the black market from databases
breached by not just outside black-hat operators, but by government and private
corporate employees seeking financial payouts. Information fences are fairly easily
contacted if you seek such information. Consider how prolifically your e-mail and
other non-medical information is made available to concerns with enough money to
buy it...
Electronics Themed Comics
Here are a four more
technology-related comics from magazines of the days of yore, this time from
a 1948 edition of Radio-Craft magazine. Readers would submit ideas for
funnies and then artist Frank Beaven would draw the comics. The page 37 comic is
an example. Evidently E.R. Donohue, of Walla Walla, Washington, had issues
with his phonograph featuring a record changer mechanism. My interest in rockets
makes me really appreciate the page 82 comic with the missile's flight being affected
by the musical "interference." In the early days of remote control, audio tones
modulated onto a carrier commanded tuning-fork-like (tuned) "reeds," which acted
as channel filters for separating and directing signals, in the airborne receiver
section to control surface actuators (see video). It is rare to find a comic in
a technical or hobby magazine these days. I don't know why that is...
Making Money in Radio - Still Possible?
Long-time RF Cafe contributor
Bob Davis sent
me a link to this very interesting and entertaining story of one man's journey (Mr. Mike
Simpson) in his effort to determine whether "Making Money in Radio" is still
as guaranteed as the vintage electronics magazine advertisements enthusiastically
asserted. To find out, he, researched and purchased a couple vacuum tube radios,
then restored them to fine quality, and then put them up for sale on eBay. In some
cases minor component replacement or repair was required. Calculations were then
made of an estimated effective hourly wage for the effort. The result may (or may
not) surprise you. As you will see on his "Analog
Dial" website, Mike has collected and restored many old radios, both production
models, kits from the era, and homebrew radios. BTW, notice in the photos that he's
a model rocketeer as well.
A bit of good humor is mixed in with the stories and descriptions. Enjoy!
Battery Types and Their Characteristics
According to Samuel Milbourne's "Battery
Types and Their Characteristics" article in Popular Electronics magazine,
in 1973 there were about 400 different battery types to choose from when deciding
what to buy for your automobile, electronic device, uninterruptible power supply,
flashlight, etc. I don't know what the number of types is today, but it must be
in the thousands. Nominal voltage, case size and shape, energy capacity (amp-hour
rating), current delivery capacity ("C" rating), environmental accommodation, connection
type (contact, solder, screw-on, or push-on terminals), chemistry, number of recharge
cycles (for secondary batteries), and a host of other choices are available nowadays.
Every time I need to order a new Li-Po battery pack for a model airplane or helicopter,
I spend quite a bit of time searching through mAh versus weight and physical size
specifications to identify the best - and most affordable - option. There will never
be a one-size-fits-all battery. If you are interested in vintage batteries...
RF Cascade Workbook
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...
Please Visit Empower RF's Website in
Appreciation of Their Support
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.
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.
About RF Cafe. I also
have an extensive list of
Recently Added topics.
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
Copyright 1996 - 2026
All trademarks, copyrights, patents, and other rights of ownership to images
and text used on the RF Cafe website are hereby acknowledged.
All trademarks, copyrights, patents, and other rights of ownership to images
and text used on the RF Cafe website are hereby acknowledged.
Contra-polar (negative) energy
Hugo Gernsback
Berkeley Nucleonics Corporation (BNC)
Exodus Advanced Communications
National Company
Empower RF Systems
