See Page 1 |
2 | of the September 2025 homepage archives. Tuesday the 30th
 Attention:
Effectively immediately, the official e-mail address for reaching me (Kirt Blattenberger)
regarding RF Cafe matters is
kmblatt83@aol.com
(was kmblatt83@aol.com).
This change is being
made in order to consolidate all e-mail into a single account for simpler management
in Outlook 2007. Where does the name come from? Kirt and Melanie Blattenberger,
married in 1983. Thanks for your cooperation.
 This
Electronics Abbreviations Puzzle appeared in the February 1959 issue of
Popular Electronics magazine. As the title suggests, answers to the clues are
entered into the Across / Down grid in the form of abbreviations - not whole words.
That make it a bit more challenging, but the puzzle's low density grid makes it
not so difficult. John Comstock, creator, provided many such puzzles to PE
readers over the years. Unlike the weekly crosswords from RF Cafe that use only
relevant technical words, this one uses some common words unrelated to electronics
and science to fill in where needed. It's still a good puzzle, though. Print it
out for use during your next boring meeting or 12-hour flight to China...
 Perhaps one of the most frustrating situations
to find yourself in if you are a
hard core audiophile is being an unmarried enlisted man in the
military, living in the barracks. Unlike residing in a college dorm where comparatively
there is no iron hand of peaceful existence enforcement to quell a desire for music
hall sound levels with bass saturation that can rock you off your chair (other than
dorm mates threatening to beat you to a pulp), in a military establishment there
is an immediate threat of arrest, rank demotion, monetary fines, or a letter of
reprimand (aka nonpunitive punishment) for blasting a stereo (and your barrack mates
might beat you to a pulp). One guy I shared a USAF barracks room with had a couple
thousand dollars worth of stereo equipment in a 19" rack in the room. It had something
like...
 "SpaceX
said the next generation of
Starlink D2C satellites will be designed to fully use the spectrum acquired
from EchoStar, with the capability of enabling 20 times the throughput capability
of its first-generation satellites. SpaceX is asking the FCC for the authority to
launch a new constellation of up to 15,000 satellites to provide direct-to-cell
(D2C) services to consumers on the ground. The company last week filed a request
with the FCC for the additional satellites, which will use 2 GHz spectrum it's acquiring
from EchoStar. The FCC still must approve the $17 billion spectrum transfer from
EchoStar to SpaceX, but given FCC Chairman Brendan Carr's statement calling it a
'potential game changer..."
 Electronics-themed comics are usually saved
for Fridays, but what the hey; maybe you need some humor on Tuesday this week. At
least three of these
antenna-based comics required a harder look to determine what
was happening and why it is humorous. One of those even requires a little technical
insight to "get it." To see my take on the comics, highlight the text...
 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!
Monday the 29th
 Carl Kohler was way ahead of his time when
he published this "Hellishcopter"
article in a 1957 issue of Popular Electronics magazine. Back in the day,
radio controlled helicopters were the privileged domain of genius electronics and
mechanical engineers and/or craftsmen. There were no commercially available kits
at all. Some free flight helicopters were on the scene using either rubber bands
or model airplane engines for motivation. Radio systems used vacuum tubes for amplification,
and servomechanisms were crude devices that were anything but linear in response
to transmitter control inputs and were quite unreliable. The "proportional" systems
used a bank...
 "Accurately estimating the
junction temperature of a semiconductor device is essential for ensuring its
reliability, performance, and longevity. Junction temperature has a direct influence
on the efficiency, stability, and safety of electronic components. This article
presents techniques for estimating junction temperature, with a focus on utilizing
thermal-resistance and thermal-characterization parameters. By following these techniques,
engineers can implement effective thermal-management strategies, enhance device
performance, and mitigate the risk of overheating-related failures. Furthermore,
the article details fundamental thermal parameters, highlights the key differences
between thermal-resistance and thermal-characterization..."
 Are you violating patent laws in your basement?
Patent laws have changed since this article was published in 1966, but the tenets
are basically the same - do your due diligence on prior work assignment before publishing
any publicly accessible product (print or physical). Since part of Popular Electronics'
raison d'être is to provide circuits for hobbyists to build and benefit from, the
lawyer who wrote this piece focuses on such applications. He claims, at least according
to 1960 patent law, "There are court decisions which hold that experimental use
of a patented invention for the sole purpose of gratifying curiosity or a philosophical
taste, or for mere amusement, is not an infringement." However...
 If it seems like the last few of these "Kirt's
Cogitation" installments were on the subject of AI (Artificial Intelligence),
there is a good reason: the last three have been. My motivation stems from having
enlisted the services of many different AI engines over the last year or so for
the primary purposes of attaining historical data on notable persons and events,
receiving explanations of science and engineering principles - including equations
- and soliciting software code snippets and/or having code snippets analyzed for
efficiency. Results vary from spot-on excellence, to devastatingly wrong. That goes
for all realms of inquiry. Other of my writings have lamented and criticized the
number of online calculators that produce glaringly incorrect...
 Just a note to say that with this new version
K of
RF Cascade Workbook, the Component Swap speed that was introduced in version
J has been significantly increased. Repeatedly calling a subroutine from within
a subroutine to swap individual cells really slowed things down. I rewrote it to
do the cell swapping locally. According to Excel's documentation, addressing a range
of cells (rather than individually) to do the swapping should work, but it doesn't
- at least not reliably...
 Anatech Electronics (AEI) manufactures and
supplies RF and microwave
filters for military and commercial communication systems, providing standard
LP, HP, BP, BS, notch, diplexer, and custom RF filters, and RF products. Standard
RF filter and cable assembly products are published in our website database for
ease of procurement. Custom RF filters designs are used when a standard cannot be
found, or the requirements dictate a custom approach for your military and commercial
communications needs. Sam Benzacar's monthly newsletters address contemporary wireless
subjects. Please visit Anatech today to see how they can help your project succeed.
Friday the 26th
 This "Holes
to the Rescue" episode of John Frye's "Carl and Jerry" technodrama series appeared
in a 1957 issue of Popular Electronics magazine. While on a fishing trip,
the two technically skilled lads discover an Air Force ham radio operator who was
injured in a car crash. Realizing the victim's conventional radio equipment had
been destroyed, they ingeniously construct an emergency communication system. Using
Jerry's new Regency transistor converter, Carl's portable broadcast receiver, and
improvised antennas crafted from their fishing gear, they create a working ham radio.
They successfully transmit a distress call which is received by an operator in Tucson,
Arizona, who contacts local authorities. A rescue helicopter arrives promptly, saving
the serviceman's life. Can you figure out why the title was chosen?
 All of the
oscilloscope measurement techniques presented in this 1960
Electronics World article apply to 2018 circuit measurements. Anyone who attended
a high school or college electronics lab has created and measured capacitance, inductance
and resonance using an o-scope as part of a classroom exercise. We all were wowed
the first time we hooked up signal generators to both the horizontal and vertical
deflection inputs and observed rotating Lissajous patterns on the display. Don't
tell me you didn't twist the frequency and amplitude knobs of the sig gens with
the delight of a kid playing with an Etch-A-Sketch. When I was taking labs in the
1970's and 1980's, school oscilloscopes were all analog...
 The newest release of
Espresso Engineering Workbook includes a Phase Noise Calculator. It will determine
the values of Total Phase Noise Power, Total Phase Variance, Phase Jitter, and Time
Jitter, based on textbook formulas that use the trapezoidal area calculation technique.
Up to 5 regions can be defined. There are scores of other handy calculators, including
filters, couplers, inductance, capacitance, Ohm's law, RF path loss, signal travel
time, complex impedance, RLC series and parallel combinations, opamps, noise figure,
skin depth...
 While not quite the equivalent of an Elvis
sighting, I was utterly surprised to see an open
Radio Shack store in the Ashtabula Towne Square Mall during a
recent trip to Ohio. As you can see in the photo, it is a shell of a store, with
products on display only along the walls. Do you remember the days when every shopping
mall and plaza had a Radio Shack crammed full of stereos, radios, calculators, antennas,
computer accessories (and the TRS-80), toys, and of course a huge portion of the
store dedicated to electronic project components? I had a "Battery Club" card for
a couple decades, and a current catalog was always on my bookshelf. If, as the old
saying goes, "Misery loves company," then the good folks at the Ashtabula Radio
Shack can at least take some solace...
• U.S. Invests
$1B in Critical Minerals
• Pirate
Radio Operator (arrrr!) Settles with FCC
• Tech
and Telecom Career Moves
• China
Exports to U.S. down 33% YoY in August
• Self-Cleaning
Glass Uses Electric
 A while back I posted a write-up on the
vintage Alliance Model U-100 Tenna-Rotor that I installed in the garage attic with
a
Channel Master CM5020 VHF / UHF / FM antenna atop it. There are
not many television antenna manufacturers around anymore; their numbers have been
decreasing continually due first to the advent of cable-delivered TV and now with
Internet-delivered TV. The "cord-cutter" movement is helping to give over-the-air
television broadcasting a rebirth due to the outrageous cost of subscription programming.
Anyone contemplating installing a television antenna today has the same concerns
as those back in 1959 when this Channel Master advertisement appeared in Electronics
World magazine - gain, directivity, bandwidth, ruggedness...
Thursday the 25th
 This "Mac's Service Shop" column, which
appeared in a 1967 issue of Electronics World magazine, captures
amateur radio's pivotal shift toward solid-state technology. The discussion
between shop owner Mac McGregor and technician cum Ham radio operator Barney Jameson
highlights how semiconductors enabled radical size and weight reductions in equipment,
transitioning bulky tube-based kilowatt stations into compact tabletop units. SSB
transmission and silicon diodes provided key efficiency gains, though transistors
still faced limitations in high-power transmitter applications due to cost and availability
constraints. The article anticipates future advancements through FETs and integrated
circuits that would improve signal handling and enable truly portable operation.
Notably, they acknowledge Japan's emerging dominance...
 As one who has used AI quite a bit in the
last year, I can attest to its utter unreliability in receiving trustworthy answers
to objective queries on matters of science, engineering, historical dates and names,
and software
code. I have fed results from one AI to another AI, and get criticisms of the
first AI from the second. It's kind of entertaining to do so. ChatGPT (OpenAI) says
Grok (X) is more intent on being your buddy and Gemini more concerned with political
correctness than providing accurate responses. That just happened last night when
querying about oscillator phase noise for a new calculator in RF Cafe's
Espresso Engineering Workbook (new version soon)...
 Nothing has change in the design and application
of
resistive attenuator pads since this article appeared in a 1959
issue of Electronics World magazine. It could be legitimately reproduced
verbatim in the August 2018 issue of any magazine. When you crank through the equations
you will arrive at resistor values slightly different from those presented here
because the author chose the nearest standard 5% tolerance resistor values. For
instance the 10 dB, T-type attenuator for 75 Ω terminations shown in Figure
7 gives series branch resistors of 33 Ω and a parallel branch resistor value
of 51 Ω. The result is an attenuator that does not present exactly the desired
input and output impedances or the exact attenuation value. More precise values
are 39.0 Ω and 52.7 Ω...
 European Microwave Week 2025 is happening
right now, running September 21-26, in The Netherlands. Please be sure to stop by
the display booths of RF Cafe advertisers: Copper Mountain Technologies (B085),
everythingRF (Pub Corner 2), Maury Microwave (B100A & B046), Reactel (B131),
Temwell Group (E130). The 28th edition of the European Microwave Week (EuMW 2025)
will come to Utrecht to continue the annual series of highly successful microwave
events that started back in 1998. EuMW 2025 comprises three co-located conferences:
Integrated Circuits Conference, Microwave Conference, and Radar Conference. Hopelijk
tot ziens!
 Exodus Advanced Communications, is a multinational
RF communication equipment and engineering service company serving both commercial
and government entities and their affiliates worldwide. Exodus'
AMP20130 is a rack-mountable High-Power Solid-State amplifier delivering >1300 W
with 61 dB gain across the 80-1000 MHz range with excellent P1dB power.
It features Class A/AB linear design, ultra-wide instantaneous bandwidth, built-in
protection circuits, extensive monitoring, large local LCD display, and remote interfaces.
Ideal for EMI/RFI, lab, CW/Pulse, and communication applications requiring high
efficiency and rugged reliability...
 Farmers must be a lot smarter than we tend
to give them credit for being. These
math and logic puzzles that appeared in the 1961 Old Farmer's
Almanac are not a duffer's task to complete. Be careful to consider units of measure
based on the venues. Puzzle I is a relatively simple trigonometry problem, although
the wording of the problem statement is very confusing; it took some head scratching
to figure out what was meant. Puzzle III required me to opt for a graphical solution
since I could not come up with enough independent equations for the number of unknowns.
If you look at the OFA page scan...
Wednesday the 24th
 Here is another tech-related crossword puzzle
for you cruciverbalists to try out on your technical cognition. Unlike the weekly
RF Cafe crossword puzzle that contains strictly engineering, science, mathematics
and other tech words, this one from Electronics World magazine does have
a few unrelated clues and words. The big difference between my making crossword
puzzles now and when Mr. Shippee made his "Crossword
Capers" puzzle is that he had to construct the grid of words manually, whereas
I just create a huge file of words and definitions, draw the grid outline, and then
click a button to have software put it all together. That's not to say my effort
is trivial, but software does cut down on a lot of time, especially...
 "There are plenty of labs working on solutions
to
Kessler Syndrome, where there's so much debris in low Earth orbit that rockets
are no longer capable of reaching it without being hit with hypersonic parts of
defunct equipment. While we haven't yet gotten to the point where we've lost access
to space, there will come a day where that will happen if we don't do something
about it. A new paper from Kazunori Takahashi of Tohoku University, in Japan, looks
at a novel solution that uses a type of magnetic field typically seen in fusion
reactors to decelerate debris using a plasma beam, while balancing itself with an
equal and opposite thrust on the other side..."
 "Who needs another
color code chart?," you might be asking. Well, as is always the
case there are new people coming into the electronics field all the time and they
are looking for resources just as we were lo those many years ago when we were first
smitten by the science. For that matter, a lot of seasoned electronics professionals
and hobbyists decide to take on the task of refurbishing or repairing vintage equipment
and need a quick reference for interpreting the colored dots and stripes on resistors,
capacitors, and inductors, as well as the colors of transformer lead wires...
Anatech Intros 3 New Filter
Models
 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 September, including a cavity
bandpass filter with a frequency range of 2200-2300 MHz, having an maximum
insertion loss of 0.8 dB, a 1000 MHz ceramic bandpass filter with a bandwidth
of 35 MHz and maximum passband insertion loss of 3.0 dB, and a 2203 MHz
cavity bandpass filter with a bandwidth of 15 MHz and maximum insertion loss
of 2 dB. Custom RF power filter and directional couplers designs can be designed
and produced with required connector...
 Electric shock, depending on severity, can
range in damage from mere discomfort to body organ damage to instant death. If you
have experience an
electric shock, you know that avoiding another incident is top
priority when working around high voltages. My worse electric shock was either the
time when I got hit with a 3-phase 440 VAC supply on an industrial air compressor
motor, or the B+ vacuum tube plate supply on the air traffic control radar systems
I worked on in the USAF. Both were, thankfully, from finger to finger or finger
to forearm (no vital organs in the current path). I've been zapped a few other times,
but nothing severe enough to require being resuscitated. Neither have I ever witnessed
anyone else being shocked to the point of needing resuscitation. There are probably
some gruesome...
 Here is another article from a vintage issue
of Popular Electronics magazine that I am posting for the benefit of Hams
who happen to be searching for information on
Swiss quad antennas. As with most topics, there are many sources
on the Worldwide Web (when's the last time you heard the Internet referred to as
the WWW?) covering how to build and tune Swiss quad antennas, but this one might
have just the right slant on things that the reader is looking for. It probably
is not of great interest to most visitors, but having it appear on the RF Cafe homepage
guarantees that Google, Bing, and other major search engines will pick it up within
hours. Thanks for your indulgence...
Tuesday the 23rd
 Before reading this 1959 "Mac's Service
Shop" episode, I had never heard of a person whose troubleshooting method was to
pull and test every tube referred to as a "Bulb
Snatcher." John Frye authored scores of these technodrama articles for various
electronics magazines from the mid 1950s through early 1970s. This one appeared
in Electronics World. Having spent my hitch in the USAF as a technician
working on airport surveillance and precision approach radar systems produced in
the early 1960s, I did a good deal of tube pulling while troubleshooting the circuitry.
Not being highly experienced at the time, I admit to having been what Mac referred
to Barney as - a "bulb snatcher." A lot of times, replacing tubes fixed...
 Satellite electron farts - what's next?
"For the first time, researchers have established a direct correlation between the
frequency of spacecraft electrical discharges and the number of electrons in the
surrounding space environment. The findings could inform future methods of protecting
satellites from potentially damaging effects. Spacecraft environment discharges
(SEDs) are short-lived electrical breakdowns that can harm sensitive electronics
and disrupt communications. They result when electrons accumulate on spacecraft
surfaces, creating uneven charging. When the voltage reaches a critical threshold,
the stored energy is suddenly released - similar to a static shock on Earth..."
 In my nearly 60 years of building model
aircraft, cars, boats, and rockets, working on cars, maintaining houses and yards,
working with electrical and electronic apparati[sic], and many other activities,
I have inhaled and had skin contact with
many types of chemicals (all legal, BTW). You probably have, too,
if you are near my age. At least by the 1960s the public was becoming aware of the
dangers of exposure to common household and workplace substances, but viewing older
pictures and films showing people working with no eye, ear, or skin protection explains
the all-too-common common sight of crippled and disfigured people back in the days.
In the early and mid 1970s I worked regularly with MEK until it was removed due
to being labeled as a suspected carcinogen...
 Do you have an FM radio in your cellphone?
If so, its antenna is the headphone or ear bud wires. You can buy an external FM
antenna that plus into the headphone jack. Do you remember the type of
line cord antenna described here? It was actually not a bad idea
in many situations. Although the appliance might look a bit scary, there is no direct
physical contact between the antenna wires and the house AC supply. Either a capacitor
with low impedance in the radio and/or television band was connected to the plug
blade or a capacitively coupled plate was placed around the AC wires to pick up
signals. 60 (or 50) cycle content on the antenna would be minimal and rejected by
the receiver front end filtering. Many of the problems people had with this or any
twin-lead transmission cable were due...
Monday the 22nd
 Since I don't have another Popular Electronics
electronics quiz for this week, hopefully these
electronics-themed comics will suffice as a workday afternoon
relief at the end of a tough work week. My favorite is the one with the Ham dude
misinterpreting advice and connecting his antenna to... well, you'll see. The other
two are pretty good as well. I colorized them for you. There is a yuge (a little
NYC lingo) list of other technology-themed comics at the bottom of the page...
 "During a video appearance at the All-In
Summit, Elon Musk answered some of the burning questions on everyone's mind these
days. SpaceX just this week inked a deal with EchoStar to buy $17B worth of AWS-4
and H-block spectrum to
connect cell phones directly to satellites. Conveniently (for us), Musk appeared
at the All-In Summit, which featured other business leaders like Mark Cuban, that
took place in Los Angeles this week. Video of Musk's appearance was uploaded to
the YouTube channel of the All-In Podcast on Tuesday. The spectrum purchase signifies
a long-term deal, he acknowledged, as the phones that support the frequencies that
SpaceX is buying likely won't be shipping for about two years..."
 The
stacked halo antenna is a compact configuration for obtaining
a nearly omnidirectional radiation pattern with nearly 8 dB of gain. An ideal
half-wave dipole antenna provides 2.15 dB, so adding 5 to 6 more decibels by
merely stacking two halo antennas (which are essentially curved half-waves) might
seem like getting more than the sum of the parts. That extra gain is obtained by
concentrating the vertical radiation pattern lower to the horizon as compared to
a straight half-wave, even though the horizontal pattern loses a bit of gain contribution
from the translation to a nearly omnidirectional nature. There is nowadays a plethora
of information available on the Internet regarding stacked halo antennas, but in
1965, this Popular Electronics article...
 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
WM2PD-0.5-6-N from Werbel Microwave is a 2-way power splitter covering the continuous
bandwidth of 500 MHz to 6 GHz. The product features low insertion loss,
high isolation and excellent VSWR performance. Tight phase matching and amplitude
balance between outputs. Aluminum body with stainless steel N female connectors.
Ready for 5G and 6G deployment. The device is RoHS compliant. Typical phase balance
of 2° and insertion...
 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...
Friday the 19th
 Anyone familiar with the history of the
Radio Corporation of America (RCA) is aware of the man responsible for its momentous
success, David Sarnoff. Mr. Sarnoff was born in Uzlyany. When he was nine years
old, his family emigrated to the United States and settled in New York City. Sarnoff
began working as an office boy for the Marconi Wireless Telegraph Company of America,
in 1906. He quickly impressed his superiors and was promoted to telegraph operator.
In this role, he famously sent the first ever radio message to a ship at sea, alerting
the crew of the sinking of the Titanic. RCA was formed to inherit the workings of
Marconi Wireless, and Mr. Sarnoff became its general manager. During World War II,
his civil and military...
 When this article on ionospheric and tropospheric
scatter radio communications was published in 1960, satellite
communications was in its infancy and only a very few subsea telephone and telegraph
cables had been laid between continents. Wideband communications was typically considered
to mean a few hundred kilohertz worth of data. Less than two decades had passed
since it was discovered that the theoretical prediction of cripplingly high attenuation
above a "smooth earth" would ultimately limit the usefulness of over-the-horizon
(i.e., not line-of-sight) HF, VHF, and UHF transmissions to a few hundred miles.
In fact, so thoroughly had the commercial broadcast community...
 This
story about the origin and definition of "The AC Volt" appeared
a many years ago in Nut & Volts magazine. I think I posted
a link to it at the time, but since new entrants to the electronics field come to
RF Cafe every day, it is worth repeating. "In the US, the DC volt is legally defined
by the Josephson array - a super conducting quantum device with a highly repeatable
output voltage. Banks of standard cells and temperature-stabilized Zener diode references
are used by the National Institute of Science and Technology (NIST) to calibrate
DC meters for scientific and industrial customers. So how is the AC volt defined?
As it turns out, there is no 'standard' AC volt in the same way there is a standard
DC volt..."
 Some day in the not too distant future,
a generation of electronics enthusiasts will read magazines like Nuts &
Volts, QST, Make, and other hobbyist publications and be
amazed at how crude our present day methods for building
homebrew projects were. They might even feel sorry for us. Having
digital cameras, sophisticated graphics software, high resolution inkjet and laser
printers, and vinyl cutting machines for adorning chassis and panels are a godsend
here in twenty-teens compared to the film-based analog cameras, chemical-based photo
processing labs, and rub-on lettering and shape stencils...
Thursday the 18th
 Electronics repair shops - what's left of
them - probably don't experience the sort of problem illustrated in this story composed
after the manner of John Frye's "Mac's Service Shop" dramas. However, similar situations
can and almost certainly do crop up in many other customer service venues. The point
of the article is how easily, especially in the span of an entire year, seemingly
minor oversights repeated with regularity, can add up to
alarmingly large numbers. Actually, the phenomenon occurs for
you with many things when you bother to tally them up. Example: According to the
U.S. census Bureau's 2017 report, the average one-way commute time is about 26 minutes
both to and from work, or about 52 minutes...
 Even though more than six decades have passed
since this article appeared in Popular Electronics magazine, the principles
and tips provided for securely and robustly
guying antenna towers still stand. Jack Darr, who wrote many PE columns on topics
including radio and television, has a pretty big bag full of tricks for installing,
operating, and maintaining equipment. His electronics theory and troubleshooting
pieces were epic back in the day when there were such things as antenna installation
crews and electronics service shops. Antenna tower design and materials have come
a long way since the welded iron and steel tubing jobs of yesteryear, as have guy
wires, turnbuckles, and anchoring hardware, but you still need a good grounding
in basic mechanics...
 If you think the ISM (Industrial, Scientific, and Medical) unlicensed bands were a relatively
new spectrum allocation, you might find this 1960 Electronics World magazine
news piece interesting. Individual countries generally acknowledge the ISM emissions
specifications set forth by the International Telecommunication Union (ITU), which
created the bands in 1947. The 900 MHz, 2.4 GHz, and 5.8 GHz WiFi bands
are well known to most people. 24 GHz is gaining traction as current spectrum
gets more and more crowded and high bandwidth data channels are needed. Interestingly,
the first few ISM bands are integer harmonics of the lowest (6.78 MHz, center
of band 1)...
 "Despite a flat market for the next couple
of years the
RF front-end module market, which was worth $15.4B in 2024, will be worth more
than $17bn by 2030, says Yole. It is being driven by 5G, new frequency bands and
early 6G rollout while facing headwinds such as architectural simplification, intense
cost pressure and declining ASPs. Chinese players are disrupting the market: Huawei,
Vivo, Xiaomi, Oppo and Honor lead a fiercely competitive Chinese smartphone market,
enabling domestic RF suppliers to scale and innovate. There is a shift towards simplification
and compactness: Chinese OEMs are shifting towards co-integration of multiple functionalities
into a smaller number of modules, reducing the BOM and PCB space..."
 Bell Telephone Laboratories was largely
responsible for designing and building a
communications system that was the envy of the world. Innovation
on the part of Bell engineers, manufacturing staff that produced the equipment,
and technicians who serviced the systems deserve the credit as do management types
who made funds and opportunity available to the aforementioned. As the number of
telephone service subscribers grew and reliability became even more vital to business,
law enforcement, and national defense, new methods had to be devised. In the late
1950s, Bell introduced the concept of wireless microwave links at 11 GHz (X
band)...
 Cesium-137, iodine-131, carbon-14, plutonium-239,
strontium-90, uranium-235, and the list goes on. These and other
radioisotopes associated with nuclear material are the result
of explosions, medical treatments, laboratory experiments, or in some cases naturally
occurring deposits. Regardless of the source, most people, including me, cringe
at the thought of being exposed to the insidious effects of the cell-altering energy
they possess. Ionizing radiation is the dangerous type of radiation due to its ability
to dislodge electrons from atoms, and in the process forming cancerous cell mutations
or killing the cells altogether. Researchers in the early days of radiation discovery
experienced sometimes gruesome maladies as a result of the handling isotopes. Some
knowingly subjected themselves to harmful doses...
Wednesday the 17th
 This 1961 Popular Science magazine
article demonstrates that
lightning protection fundamentals remain unchanged: ungrounded antennas attract
strikes rather than prevent them. Modern understanding confirms that lightning seeks
the path of least resistance to ground, and protection still relies on providing
that path through low-impedance conductors. While 1961 specifications called for
#8 copper cables and deep ground rods, today's National Fire Protection Association
(NFPA 780) standards maintain similar principles with updated materials and installation
practices. Modern systems still use air terminals, down conductors, and grounding
networks, though we now incorporate enhanced bonding techniques and surge protection
devices...
 "Graphene,
a single sheet of carbon atoms arranged in a honeycomb lattice, is known for its
exceptional strength, flexibility and conductivity. However, despite holding the
world record for room-temperature electron mobility, graphene's performance at cryogenic
temperatures has remained below that of the best GaAs-based semiconductor systems,
which have benefited from many decades of refinement. One key obstacle is electronic
disorder. In practical devices, graphene is highly sensitive to stray electric fields
from charged defects in surrounding materials. These imperfections create spatial
fluctuations in charge density, known as electron-hole puddles, that scatter electrons
and limit mobility..."
 A news story with a title about a boat and
reverse current is more likely to be referring to water flow in a river or stream
than about electrical current in a conductor. Having grown up in a neighborhood
next to a tributary of the Chesapeake Bay, I spent quite a bit of time around boats,
both large and small. Salt water is particularly destructive to metal hulls due
to
cathodic corrosion, exacerbated by the salt water's conductivity.
While working as an electrician in the 1970s, I installed electrical supplies for
a few dockside cathodic protection system that probably functioned like the one
described in this 1965 issue of Popular Electronics magazine. The principle
is fairly simple whereby anodes are placed in the water around the hull and a counter-current
is induced...
 Television (TV) and high fidelity stereo
(HiFi) were a big deal from the 1950s through the 1970s as
electronics technology underwent major improvements in component
capabilities and research produced high-complexity circuits that featured sophisticated
methods of signal processing. The industry went through the transition from vacuum
tubes to transistors during that three decade period, setting the groundwork for
the next generation of microprocessor-based audio-visual entertainment. Printed
comics and TV and radio shows favorite themes included jokes having to do with Joe
Sixpack and his family's anecdotes involving television and HiFi stereo. Here are
a few more from the mid-1960s...
Tuesday the 16th
 This
Roundword Puzzle is not as challenging as a crossword puzzle, but it is a useful
exercise to check how rounded out your knowledge of basic electronics principles.
Author Leonard Kindler (I call him "Leo") provided this for Popular Electronics
magazine in 1961. As Leo states, if you are fairly capable are electronics theory
(nothing on a PhD level), then it will not prove too difficult. Below the Roundword
Puzzle is a huge list of other puzzles in various formats that I have posted here
on RF Cafe (many I created myself). BTW, when I first saw the title in the table
of contents, I thought it said "roundworm." Bonne chance, viel glück, go n-éirí
an t-ádh leat, buona fortuna, buena suerte...
 Just
when you thought ESD had been fully handled, along comes
die-to-die issues. "Advanced system on a chip (SoC) components use multi-die
package technologies where single silicon chips are assembled on top of each other,
beside each other on a larger interposer, or by combining various 3D packaging methods
together. Connections between chips are formed by utilizing multiple technologies
such as flip chips, substrates, interposers, silicon bridges, bond wires, micro
bumps, and through-silicon-vias (TSV). A single SoC can have hundreds to thousands
of external connections between a component package and a printed circuit board
(PCB). These connections..."
 With a fair helping of chagrin, I admit
to being a "10-4 Good Buddy" type of Ham radio operator. That moniker is applied
liberally by pre-1991 (February 14, to be exact) amateur radio licensees to post-1991
licensees because that was the year in which the FCC no longer required aspiring
Hams to pass a
Morse code proficiency test for an entry level license. It was
a sort of Valentine's Day gift. In 2003, the ITU announced the rescinding of its
code requirement and allowed countries to set their own standards. By 2007, General
and Amateur Extra exams no longer required code tests. I earned my Technician license
in 2010...
 A lot of nostalgia gets waxed here on RF
Cafe, to which frequent visitors can readily attest. Old timers (if you're not one
now, you some day will be) often like to see remembrances of days of yore, the halcyon
days of past hobbies, family, long naps, school (yuk), vacations, and other pleasurable
times. Hopefully, you already have or will soon have a few of your own. This 3-page
Lafayette Radio Electronics spread from a 1965 issue of Popular
Electronics magazine is typical of what what avid electronics hobbyists would
have read and drooled over with so many great items in the offering. If you were
like me, the cost of most of the things I wanted were well outside my budgetary
reach. Prices for electronics gizmos were quite high...
 KR Electronics has been designing and manufacturing custom filters
for military and commercial radio, radar, medical, and communications since 1973.
KR Electronics' line of filters includes lowpass, highpass, bandpass, bandstop,
equalizer, duplexer, diplexer, and individually synthesized filters for special
applications - both commercial and military. State-of-the-art computer synthesis,
analysis, and test methods are used to meet the most challenging specifications.
All common connector types and package form factors are available. Update: KR Electronics
has been acquired by NIC, where KR Electronics'
legacy of quality and innovation will continue to thrive, offering the same trusted
products and services under NIC's leadership...
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. Some quoted items have been shortened
to save space. About RF Cafe.
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