See Page 1 |
2 | of the September 2025 homepage archives. Monday the 15th
 In this installment on the continuing technodrama
of
Mac's Service Shop, the subject of "Talking Books" comes up because of a special
type of record player in for repairs. The machine was a special design used by blind
people to listen to books that have been recorded by sighted readers. There is a
least a bit of irony in how the two were admiring the robustness of the design in
order to cause as little inconvenience to blind users, and yet there it was in the
shop for repair! Little could Mac and sidekick technician Barney have imagined how
far the concept would have come by today. While the physical volume, weight, and
relative cost have come way down, the capability and quality have skyrocketed. Reader
devices today can do a real-time text-to-audio translation, with some even able
to turn pages...
 "Researchers based in Singapore have achieved
a breakthrough by creating the first gallium nitride (GaN) transistors on silicon
that can operate in the
D-band frequency range (110–170 GHz) - an important step toward future 6G wireless
networks and other sub-terahertz (sub-THz) technologies. The work, reported in IEEE
Electron Device Letters by a team from Singapore's Nanyang Technological University,
the National Semiconductor Translation and Innovation Centre for Gallium Nitride
(NSTIC), the Institute of Microelectronics, the National University of Singapore,
and the Singapore-MIT Alliance for Research and Technology, marks the highest frequency
yet demonstrated for GaN-on-silicon devices..."
 It's time for another pop quiz (does that
line give you a fearsome flashback to your school days?). Whenever I have one available,
I like to post quizzes from vintage electronics magazines, like this one on diode
circuit functions which appeared in the August 1965 issue of Popular Electronics..
Many from that era include vacuum tubes, but this one has the solid state symbols
so the under-40 folks won't be uncomfortable. Your job is to look at the diode circuits
and match them with the names of the functions. A couple of them will probably cause
some head scratching, but you should do well. Don't jump to a quick conclusion with
circuit "E" without noticing the two signal generators attached to it. If you like
diode quizzes, here is another...
 Restoring and/or upgrading vintage radio
receivers is still a very popular pastime for hobbyists, and for that matter for
some professional servicemen who preform maintenance on established equipment installations.
Three of the most significant changes that can be made to older receivers to
improve sensitivity are to clean up the power supply DC output,
replace noisy components like vacuum tubes and leaky capacitors, and tune / modify
/ replace RF and IF filters. This article discusses a method of replacing a stock
LC filter with a high selectivity mechanical filter. The nice thing about an analog
receiver is that narrowband, steep-skirt filters can be substituted without concern
for group delay at the band edges that can (and will) wreak havoc on digital signals..
 Sugar Grove, West Virginia, is within the
U.S.
National Radio Quiet Zone (NRQZ), which also encompasses the Green
Bank, WV area. It was established by the Federal Communications Commission (FCC)
in 1958 to protect hypersensitive, cryogenically cooled radio astronomy receivers
from manmade terrestrial signal sources. As you can imagine, there are not many
places remaining in human-inhabited regions of earth that are not massively invaded
by radio frequency energy. If you visit the area today, you had better not have
your cellphone, computer, or other RF-producing device turned on or you can be subject
to a hefty fine. Roving signal detecting trucks monitor the region for offenders.
This 1961 report on advances in electronics also features the world's first computerized
bank check...
Friday the 12th
 This handful of
Ham-related comics appeared in the November 1965 issue of Popular
Electronics. One of them has an operator using "oboe" as the phonetic alphabet version
of the letter "O." Having never seen that before, I did a search and learned that
the British Forces in World War II uniquely used "oboe" for the letter "O."
Maybe the artist, Walt Miller, was either a member of the British Forces or hung
around (or served in the military) with someone that was. For that matter, using
"able" for the letter "A" is also a British thing. This Silent English phonetic
alphabet is interesting. I guarantee you'll appreciate the others as well, or double
your money back...
 "The future of wireless communication is
today being sketched out in the skies and in space. A new generation of intelligent
aerospace platforms - drones, airships,
and satellites - will be part of tomorrow’s 6G networks, acting as, in effect,
base stations in the sky. They're expected to roll out in the early 2030s. Researchers
at the King Abdullah University of Science and Technology (KAUST) in Thuwal, Saudi
Arabia, are amid the vanguard of innovators now imagining next-gen telecom networks
in the atmosphere, the stratosphere, and orbit. The sky won't be the limit for next-gen
wireless platforms..."
 Explaining the working of the
Trinitron color cathode ray tube (CRT) with black and white pictures
is a little like explaining a fourth dimension within the confines of three dimensions.
How do you visualize red, green , and blue in shades of gray? It's like being told
to grasp the concept of tesseract being the 3-D projection of a 4-D cube. Still,
that was the challenge author Forest Belt had when writing this article for a 1972
issue of Popular Electronics, an era where multicolor print was the realm
of high-end glossy-page magazines. Those of us who were around in the days when
Sony's Trinitron hit the market remember well the hype that surrounded it. Of course
my parent's B&W television suffered the same handicap as this printed page when
the commercials...
• AT&T
Wants out of Mexico
• Manufacturing
Contraction Slows in August
• Hams Track Down
Severe
EMI Source
• FCC
Deregulatory Efforts Continue
• Radiation-Hardened
Chips Large Hadron Collider
 J-pole antennas (aka "J" antennas) are so
named due to their physical shape. The basic "J" antenna is a half-wave vertically
polarized antenna that has an integrated parallel feed quarter-wave tuning stub.
It is very popular with amateur radio operators and is still used with some commercial
radio installations. The azimuth radiation pattern and gain are very similar to
the half-wave dipole antenna, as shown in the Wikipedia plot below. The J-pole was
invented in 1909 for use on the German Zeppelin airships as a trailing wire antenna.
Variations of the J-pole have evolved over the years that in some cases significantly
change the radiation pattern, but the characteristic quarter-wave stub match is
retained in all of them...
 Windfreak Technologies designs, manufactures,
tests and sells high value USB powered and controlled radio frequency products such as
RF signal generators, RF synthesizers, RF power detectors, mixers, up / downconverters.
Since the conception of WFT, we have introduced products that have been purchased
by a wide range of customers, from hobbyists to education facilities to government
agencies. Worldwide customers include Europe, Australia, and Asia. Please contact
Windfreak today to learn how they might help you with your current project.
Thursday the 11th
 It should come as no surprise that in the
pre-safety-ground era which included the 1960s that electrical
shocks of patients in hospitals was not uncommon. If the jolt came intentionally
from a cardiac defibrillator, then it would be a good thing. However, these shocks,
which were the subject of a Time magazine story in the April 18th, 1969
issue cited by Mac's technician, Barney, were being administered unintentionally
by patient monitoring and ancillary life-sustaining equipment. Per the article,
no Underwriter's Laboratory (UL) certification was required for hospital equipment.
Maybe it was felt that it wouldn't be so bad if someone got zapped in the hospital
since there would be a doctor on-hand to resuscitate the zapee. Since that time
medical equipment has been required to undergo stringent safety conformance requirements
that makes electrocution virtually impossible. Now, if we could just keep doctors
from cutting off the wrong limb or removing the wrong organ...
 "U.S. Space Command headquarters is being
moved to Huntsville, Alabama, known as 'Rocket City USA.' The move was announced
in a press conference on September 2, 2025. Huntsville will host the 2026 ARRL National
Convention as part of the Huntsville Hamfest, but there's a bigger connection between
U.S. Space Command and amateur radio. Space Command utilizes forces such as the
U.S. Space Force to accomplish its command mission. The ARRL Lab supports the
U.S Space Force's Phased Array Warning System (PAVE PAWS) early warning radar
installations which scan the skies for incoming missiles and space junk. Since 2007,
the ARRL Lab has been conducting this crucial analysis using Longley-Rice..."
 Here for your enjoyment at the end of another
week are three more vintage
electronics-themed comics - this time from a 1966 issue of
Popular Electronics magazine. The "quarter-inch Mylar" referenced in the title
is recorder tape used in the very popular machines of the day. Not only were serious"
music aficionados huge proponents of the medium, but so were the many recreational
users. There was a sort of mystique involved with being able to record and instantly
play back even normal conversations - sort of like with videos these days, except
there is no mystique anymore because most users couldn't care less about the technology
which enables their proclivities...
 Looking forward is essential for the advancement
of technology, but looking backward to see from whence we came is beneficial as
well. That is why I post so many articles from vintage tech magazines. Not only
does familiarizing yourself [hopefully] help prevent making the same mistakes over
again, but it give you an appreciation for the sacrifices and innovations that paved
the way to the current state of the art. The same argument can be made for social
sciences and politics. Unlike social scientists and politicians, technologists do
actually learn from the past. What caught my attention in this "Zero-Beating the News" feature in a 1966 issue of Popular
Electronics magazine was the photo of IBM engineers integrating...
    Incredibly, 24 years have passed
since the extremist Islamic attack on American soil on the morning of
September 11, 2001. Nearly 3,000 citizens died that day. World leaders have
embarked on a path of colonizing our homelands with groups of people that are known
to harbor sympathies for the terrorists. They dwell amongst us now and mean to do
us harm when opportunity presents itself - which it has on numerous occasions in
the past many years. Never forget the people who died in the burning towers, the
Pentagon, and the airplanes, and those left behind to grieve and get on with life.
Never forget the police and military members who fought - and some died - to keep
us safe and free. Never forget the rotten politicians who imperil our existence
with their selfish agendas.
Wednesday the 10th
 Former Nazi Germany's famed rocket scientist
Dr. Wernher von Braun's 1963 Popular Science magazine column answers
questions submitted by reader representing the overwhelming public interest in space
science, which motivated his monthly contributions to share complex topics accessibly.
He explains that steering large rockets involves deflecting exhaust thrust via swiveling
nozzles or jet vanes, contrasting liquid and solid propellant methods. Astronauts
exit pressurized cabins using airlocks, depressurizing the compartment before venturing
into space. Liquid hydrogen's efficiency as fuel stems from its high energy release
and low molecular weight, yielding superior exhaust velocity. Von Braun also touches
on the moon's likely sterility, solar flares' hazards to manned missions, and the
sun’s volatile activity, emphasizing space science’s interdisciplinary and dynamic
nature. This is the first of two articles submitted...
 "Researchers have developed a solar thermoelectric
generator that is 15 times more efficient than the most advanced devices currently
available. Researchers seeking greater energy independence have explored
solar thermoelectric generators (STEGs) as a potential way to produce solar
electricity. Unlike the photovoltaic cells found in most solar panels, STEGs can
capture various forms of thermal energy as well as direct sunlight. These devices
consist of a hot side and a cold side separated by semiconductor materials, and
the temperature difference between them generates electricity through the Seebeck
effect. However, widespread use of STEGs has been limited by their low efficiency..."
 Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed crossword puzzle using only words from my custom-created
lexicon related to engineering, science, mathematics, chemistry, physics, astronomy,
etc. You will never find among the words names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort. You might, however,
see someone or something in the exclusion list who or that is directly related to
this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively. Enjoy!...
 ISOTEC Corporation, a leading manufacturer
of non-magnetic, cryogenic RF connectors and cable assemblies for the Quantum Computing
industry, will be exhibiting at
Quantum World Congress 2025, being held at Capital One Hall in Tyson, Virginia,
USA. Specific interconnect features are required including ability to withstand
Cryogenic (very low) temperatures as well as being non-magnetic with high-frequency
and low loss. ISOTEC offer a range of high quality cryogenic and non-magnetic RF
components with the capability of performing at extremely low temperatures. Connectors
are manufactured under strict quality controls and this strict adherence to quality
control ensures all precautions are taken to avoid any contact...
 Usually an article about
clean layout techniques would be about printed circuit board layout;
however, this one refers to chassis layout. Having built many electronics chassis
in my days as an electronics technician (prior to earning an engineering degree),
I have a great appreciation for a professional-looking job. Some of the work done
by hobbyists that appear in magazines like QST, Nuts & Volts,
and the older titles like Poplar Electronics looks pretty darn nice - both
for kits and homebrews. It's a short article, but worth a quick look...
Tuesday the 9th
 This exercise would make a good laboratory
experiment for high school or junior college electronics courses. The required components
are still readily available - Borax is in the cleaners aisle of the grocery store.
In the days before vacuum tubes, when scientists had a need to
rectify alternating current power supplies they used chemical
devices similar to the one described here. Ironically, this chemical rectifier is
a form of semiconductor diode; albeit in a liquid state rather than in the eventual
solid state. Note that the rectifier symbol in the schematic is actually the chemical
device created in the first step - not a vacuum tube as it might appear to be...
 Werbel Microwave began as a consulting firm,
specializing in RF components design, with the ability to rapidly spin low volume
prototypes, and has quickly grown into a major designer and manufacturer with volume
production capacities. Werbel is proud to announce its model
WMC-2-8-20dB-S, a 20 dB directional coupler that covers 2 to 8 GHz
with broadband flat coupling response, high directivity, and excellent return loss
performance. Typical coupling ripple flatness is ±0.5 dB typical. Insertion
loss 0.28 dB typical. Directivity 22 dB typical. Return loss 24 dB
typical minimizes reflections. The frequency range is used extensively in Wi-Fi
testing and covers both S band and C band in one package. Assembled and tested in
USA. Enclosure measures 2.00 x 0.69 x 0.38 inches and has SMA female connectors...
 ""You
very likely saw the news in April that China's Contemporary Amperex Technology Ltd.
(CATL), the world's largest electric-vehicle battery maker, announced a super-fast
charging battery that it claims can deliver a
520-km range with just five minutes of charging. The company noted that this
world's first LFP battery features both an 800-km range and 12C peak-charging rate.
It also said that the multiple proprietary technology advances these batteries incorporate
support the high charging rate without compromising energy density, cycle life,
or safety. It is a worthwhile news item, for sure. As expected, the story, based
on a press conference, got lots of attention..."
 Many people end on RF cafe as a result of
a Google (or other) search about electronics, so even though regular visitors might
find this primer on
Ohm's law to be redundant review, it will be valuable to the aforementioned
people. Electronics technology has moved forward at lightning speed in the last
century, but the fundamentals of Ohm's law remain unchanged. Indeed, we would be
in trouble if voltage no longer equaled the product of current and voltage (E = I x R).
National Radio-TV News magazine was published monthly by National Radio
Institute, a correspondence school that did business from 1914 through 2002. A bonus
electronics-themed comic is included...
 Here is installment #3 of the four sets of
reader submissions of inane remarks (ostensibly) uttered by
electronics-challenged nincompoops. One of the funniest - and
even believable - is about 300-ohm twin lead antenna wire flattening out the picture
with color television. If you have funny anecdotes you would like to have published,
send them to me and I'll be glad to add a few seconds to your lifetime allotment
of 15 minutes of fame...
Monday the 8th
 Clarence Martin's 1965 Mechanix Illustrated
magazine "A
Guide to Hand Saws" guide offers a comprehensive overview of hand saws, emphasizing
their enduring utility despite the rise of power tools. The article traces the evolution
from primitive flint saws to modern designs, highlighting Henry Disston's revolutionary
skewback innovation. It details the primary saw types: crosscut and rip saws for
general carpentry, back and dovetail saws for precision joinery, and specialized
varieties like plumber's, coping, compass, and keyhole saws for specific tasks.
The guide also covers outdoor tools like bow saws and pruning saws, as well as metal-cutting
hacksaws...
 "Researchers from Virginia Tech have published
a new paper that outlines a vision for the future of wireless networks – one that
depends on integrating next-generation artificial intelligence with human-like common
sense. According to Walid Saad, professor in the College of Engineering and Next-G
Wireless Lead at the Virginia Tech Innovation Campus, current AI systems lack the
essential ingredient that humans use effortlessly: common sense. The paper argues
that a true revolution in wireless technology won't happen until AI can think, imagine,
and plan much like humans do. Published in the Proceedings of the IEEE Journal's
Special Issue on the Road to 6G, the paper presents a forward-looking blueprint
for creating
intelligent wireless networks..."
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's "Tech Industry
Headlines" column on the RF Cafe homepage. For the sake of all the avid cruciverbalists
amongst us, each week I create a new technology-themed crossword puzzle using only
words from my custom-created related to engineering, science, mathematics, chemistry,
physics, astronomy, etc. You will never find among the words names of politicians,
mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You
might, however, see someone or something in the exclusion list who or that is directly
related...
 RF Cafe
visitors might find this interesting, so...
My daughter and her husband bought
an 11-acre chunk of a small, retired dairy farm in North Carolina a few years ago.
Their property included all of the original buildings, including the house, a large
workshop, farm equipment shed row, milking stalls, milk processing area, hay storage,
a chicken house, and a few other structures. Nearly everything is at least 50 years
old - and it shows. There are
two active wells on the property - one next to the house, and another in a field
next to a utility building. They are independent, but there is a pipe connecting
the two systems, with a valve in between to isolate them if necessary. The photo/drawing
to the right shows, schematically, what we believe, based on testing, to be the
water line layout. The valve was originally open, and then one day there was no
water service. With two pumps in parallel, if one pump fails the other will supply
sufficient water for all needs in what is now a domestic setting...
 The
Old Farmer's Almanac (OFA) has been on my annual need-to-buy list
for as long as I can remember. It is chock full of useful data for sunrise and sunset
times, high and low tide times, crop planting days, first and last frost days, and
significant astronomical events. There are stories of interest on topics ranging
from canning your garden's harvest to how to view a solar eclipse. - often from
noted authors, but also from lay people. I also enjoy the monthly "on this day"
type tidbits and the homey short story relating to the time of year. After 225 years
of continuous publication, it still features the hole in the upper left corner to
facilitate handily hanging it on the wall of your shed -- or outhouse. I gave a
1961 edition of the Old Farmer's Almanac found on eBay to Melanie as a
birthday present this year...
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Exodus'
AMP20063 is a rugged SSPA incorporating advanced technology for 6.0 to 10.0 GHz
applications. Class A/AB design for all industry standards, 100 W minimum with
50 dB gain. Excellent power/gain flatness, Forward/Reflected power monitoring
in both dBm & watts, VSWR, voltage/current, and temperature sensing for superb
reliability and ruggedness. Instantaneous ultra-wide bandwidth, built-in protection
circuits with extensive monitoring. Nominal weight is 45 pounds in a compact
3U chassis, 5.25" H x 19" W x 27" D...
Friday the 5th
 Although not entirely necessary to enjoy
this story, it occurs to me that many people reading it might not know how to compare
the size of a "man cookie" to a 45 rpm record - or for that matter even know
what a record is (other than a unit of database storage). A 45 rpm record (single)
is 7 inches in diameter, as opposed to a 33-1/3 rpm (LP 'long playing'
album) which is 12 inches. Now you can get past the opening paragraph and glean
the advice offered by electronic repair shop owner Mac McGregor regarding seeking
out
repair services. It applies to automobiles as well as electronics.
The really interesting point I found, however, was his quoting of a 1970 statistic
claiming that by 1980 the U.S. would employ more service employees than manufacturing...
 If you like word puzzles, then maybe you'll
want to give this
word search with names of common electronics components hidden
within a matrix of random letter a go. It appeared in a 1965 issue of Popular
Electronics magazine. Keep that in mind while searching for the Mystery Word
(we old-timers will recognize it with ease). Enjoy...
 Carleton Phillips was not minimizing his
predecessors when he wrote this 1966 Popular Electronics article marveling
at the accomplishments in "Gay Nineties" (1890's) in spite of their relatively crude resources.
Seven decades had passed since then. A similar article could be written today, five
decades hence, about today's knowledge and technology compared to that of the mid
1960's. For instance, DNA had not yet been sequenced, 3D printing did not exist,
Al Gore had not invented the Internet, MRI machines were not available, there
were no cellphones, PC's were only a dream, booster rockets could not land self-powered
for re-use, TV's used CRT's...
• ARRL
and RRI (Radio Relay International) Sign Agreement
• U.S. Space Force Developing
Global Secure Satcom Network
• OpenAI
Users Not Happy About GPT-5
• Steel
Quota Cuts Causing Supply Chain Disruption
• Three More
Private 5G Projects
 IPP-8057 is a 150 Watt (average power),
surface-mount, dual directional coupler that covers 500 to 2500 MHz (0.5 to 2.5
GHz). The 0.50 x 1.00 inch coupler has a nominal coupling value of 33 dB, >20
dB of directivity, <0.25 dB insertion loss, coupled flatness of ± dB
and VSWR less than 1.25:1. IPP directional couplers can be used to sample RF power
in a multitude of applications and are available as dual-directional couplers (DDC),
single-directional couplers (SDC), and bi-directional couplers (BDC). They can also
be customized to add multiple forward and reverse power sample ports...
Thursday the 4th
 Any day is a good day for Carl and Jerry
stories, Mac's Electronics Service Shop sagas, Hobnobbing with Harbaugh, electronics-themed
comics, electronics quizzes, and other forms of nerd entertainment. Here is another
of Robert P. Balin's great challenges titled, "Diagram Quiz." Most RF Cafe visitors will easily identify eight
or nine of the ten diagrams. Relatively few will be familiar with the Rieke diagram.
The Biasing diagram is a bit misnamed IMHO, and could cause confusion. Bon chance...
 My newest release of
RF Cascade Workbook (vJ) has added the ability to
swap all input parameters of any two stages!
This has been a much-requested feature - something that Excel does not have as a
built-in feature. After battling the quirkiness of Excel VBA code, I arrived at
what appears to be a reliable implementation. This adds a great deal of usefulness
and eliminates errors that tend to creep in when manually swapping component positions.
I also added a worksheet for a project-level bill of material (BoM). A free upgrade
is available to anyone who purchased any version of RF Cascade Workbook 2018;
just send me an e-mail (of course you could benevolently pay for a new copy and
help this old man deal with the massive inflation that occurred from 2020 to 2024).
A sample version is available for download...
 Here are a couple more
electronics-themed comics from the March 1967 issue of Popular
Electronics magazine for your TGIF enjoyment. The comic on page 100 especially
appeals to me since I am finishing the installation of a Channel Master CM-5020
antenna. It has been a long time since I installed a traditional style TV antenna
- about 40 years ago when I put a Radio Shack antenna on the roof of my mother's
house. The entire 109" long by 100" wide antenna, including mounting hardware, weighs
only 11.5 pounds and presents a wind resistance of 30 pounds. This is Channel
Master's best antenna. Gain is 10 dB at VFH and 16 dB at UHF. I plan to
use it for FM radio as well. A vintage Alliance Tenna-Rotor will make it steerable...
 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 filter models have been added to the product line in August,
including a 2350 MHz cavity bandpass filter with a 320 MHz bandwidth,
a 1000 MHz ceramic bandpass filter with a 35 MHz bandwidth, and a 400 to 2500
MHz cavity highpass filter. 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.
 As far back as 1966 electronics hobbyists
knew that silicon bathtub caulk was an excellent flexible insulator for electronics.
It originally went by the name "Silastic," which is a portmanteau of "silicone" and "plastic,"
and is a type of RTV (room temperature vulcanizing) compound. It has a typical voltage
withstanding of over 400 V/mil, or 400 kV/inch, which is why it is used
extensively on high voltage connections. Dow Corning, its inventor, still sells
various compounds of Silastic both as an insulator and as a molding compound. I
used it at Westinghouse Electric in the 1980's to seal metal molds for overmolding
towed sonar transducer arrays...
Wednesday the 3rd
 A lot of RF Cafe visitors might not be familiar
with some of the electronic devices presented in this
Electrochemistry Quiz by Popular Electronics' resident
quizmaster, Robert Balin (a big list of his other quizzes is at the bottom of the
page). I offer my assistance. A is a photocell, B is an early type of rectifier,
C is a varistor, D is a cathode ray tube (CRT), E is an electrolytic capacitor,
F is a heated cathode in a vacuum tube, G is a flashlight battery, H is an early
receiver crystal detector, I is a magnetic audio recording tape, and J is phonograph
cartridge. I scored...
 "'This is the first demonstration
of a
transfer-free method to grow 2D devices,' claimed researcher Sathvik Iyengar
(pictured). 'This is a solid step toward reducing processing temperatures and making
a transfer-free 2D semiconductor-integration process possible.' Serendipity had
a hand in the discovery. 'We received a sample from a collaborator that had gold
markers patterned on it,' said fellow researcher Lucas Sassi. 'During CVD [chemical
vapor deposition] growth, the 2D material unexpectedly formed predominantly on the
gold surface. This surprising result sparked the idea that by deliberately patterning
metal contacts, we might be able to guide the growth of 2D semiconductors directly
across them...'"
 For the sake of all the avid cruciverbalists
amongst us, each week I create a new
technology-themed crossword puzzle using only words from my custom-created
lexicon related to engineering, science, mathematics, chemistry, physics, astronomy,
etc. You will never find among the words names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort. You might, however,
see someone or something in the exclusion list who or that is directly related to
this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively. Enjoy!...
 According to this 1972 article in Popular
Electronics, there were as many as 50,000 computers in the world at the time
using
magnetic core memories. Among them was the Apollo Guidance Computer
that was onboard the Apollo 11 Lunar Module that Neil Armstrong used in July
1969 to land on the moon. Semiconductor memories were being manufactured in 1972,
but believe it or not they were not as fast as the magnetic core memories. Machinery
was not available with enough precision and repeatability to thread the read, write,
sense, and inhibit wires...
Tuesday the 2nd
 Everyone who is interested enough in
microwave diodes to read this article surely knows* what IMPATT, GUNN, and PIN
diodes are, but have you heard of Read-effect, TRAPATT, LSA, or QMD diodes? If not,
it is likely because you entered the microwaves field long after 1969 when this
edition of Electronics World was mailed to subscribers. Device improvement
and obsolescence accounts for familiarity with the former and unfamiliarity with
the latter, respectively. The article below by two Sylvania Electronic Products
engineers describes the properties of various up-and...
 Who else remembers listening to your dial-up
modem sing its digital tune as it connected you to the World Wide Web (WWW)? Who
else used to grab the free
AOL CDs in the 1990s
at the Wal-Mart - or Wal*Mart - (which is how it was spelled during the era)
electronics counter free extra hours of connectivity? This IEEE Spectrum article
provides the back story of its so-to-be demise. "The last time I used a dial-up
modem came sometime around 2001. Within just a few years, dial-up had exited my
life, never to return. I haven't even had a telephone line in my house for most
of my adult life. But I still feel a strong tinge of sadness to know that AOL is
finally retiring the ol' hobbyhorse..."
 The metal-oxide-semiconductor field-effect
transistor (MOSFET) was patented in its present form by Bell Labs in 1959,
following the original patent by inventor Julius Edgar Lilienfeld, in 1925. It had
only been on the open market for designers to use for a bit over a decade when this
article appeared in Popular Electronics. Adolph Mangieri wrote a number
of articles for the magazine in the early 1970s introducing readers to the many
new types of semiconductor devices coming out of research laboratories and into
the commercial marketplace; e.g., "Understanding the Junction Field Effect Transistor."
MOSFET's are nowadays the primary building...
 Each week, for the sake of all avid cruciverbalists
amongst us, I create a new
technology-themed crossword puzzle using only words from my custom-created
lexicon related to engineering, science, mathematics, chemistry, physics, astronomy,
etc. You will never find among the words names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort. You might, however,
see someone or something in the exclusion list who or that is directly related to
this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively...
 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.
Monday the 1st
 Glass-encapsulated bi-reed magnetic switches
were a relatively recent invention that came out of Bell Labs when this
Carl & Jerry episode was published in Popular Electronics magazine
in 1962. It seems like such simple and common components have been around forever,
and they have for a growing portion of people in the electronics realm since that
was more than half a century ago. As is often the case with John Frye's enterprising
pair of teenage experimenters, the reader is treated to a tutorial on the operational
theory of the switch, with its dependence on magnetization by induction. The story
ends up being quite humorous, and reminds me a bit of the old All in the Family
episode where a window salesman uses a photography light measuring meter to convince
Archie...
 "MIT researchers have developed a reconfigurable
antenna that
dynamically adjusts its frequency range by changing its physical shape, making
it more versatile for communications and sensing than static antennas. The antenna
can be stretched, bent, or compressed to make reversible changes to its radiation
properties, enabling a device to operate in a wider frequency range without the
need for complex moving parts. With an adjustable frequency range, the reconfigurable
antenna can adapt to changing environmental conditions and reduce the need for multiple
antennas. The word 'antenna' may draw to mind metal rods like the 'bunny ears' on
top of old television sets..."
 It's a good thing that ferric chloride does
not turn unstable and explosive after sitting in the dark for many years or I might
be in trouble. My bottle was bought back when Radio Shack was the electronic hobbyists
local source for project parts. There is probably not much demand for either ferric
chloride, FeCl3, or ammonium persulfate, (NH4)2S2O8,
these days since fewer people are making their own printed circuit boards (PCB's)
and there is a host of companies who offer low quantity
PCB fabrication at a good price. However, for those who still
engage in home brew projects and want an alternative to point-to...
 As one who enthusiastically followed the
manned space program from its early days in the 1960's, reading
news stories and magazine articles on new technology and research never ceases to
amaze me. When China or Russia flies the next man to the moon, the level of fanfare
will be more focused on how the U.S. is no longer considered the leader than on
how much more improved technology is and how much lower the risk is. We now have
over a million total hours of men living in space versus a thousand or so in 1969.
Semiconductors have totally replaced vacuum tubes - with vastly better capability
and ruggedness. Mechanics and...
These archive pages are provided in order to make it easier for you to find items
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