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 You probably need to be a
Ham radio operator to fully appreciate the humor in some of these
comics. The first one, for instance, is a poke at a guy proudly pointing out his
QSL cards from distant (DX) stations "right near the city limits," "on the other
side of town," etc., basically what you can pull in with a home Citizens Band (CB)
radio base station and a rooftop antenna. In another, the "73" signoff code is from
the Western Union telegraph standard meaning "Best regards." "88" means "Love and
kisses," hence the guy's unnerved response. The others don't really require
an insider viewpoint. Let me know if you need any more help ;-)...
 At least 10 clues with an asterisk (*)
in this
technology-themed crossword puzzle are pulled from this past week's
(7/16 - 7/20) "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 list 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...
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 Any time I see an article that references
causing limb movements by poking the brain with electrical signals, I think of the
old The Far Side comic. Artist Gary Larson drew quite a few hilarious operating
room scenarios.
Electrocution is of course not a laughing matter - unless it happens
to someone else and it is not serious and no harm is done. Then - and only then
- can it be funny. I've laughed at myself many times after receiving a good
jolt due to stupidity. Sometimes after such an experience I wonder how I never killed
myself from getting zapped as the result of being too lazy to turn off a circuit
breaker before servicing a light switch or receptacle. The sad thing is that I'll
probably do it again some day...
 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.
 Popular Electronics magazine printed
in April 1966 its first notice of
new frequency units to be used beginning with the June edition.
The May issue included this piece titled, "Comes the Revolution - or - '40 Million
Frenchmen Can't Be Wrong'." Predictably, not everyone liked it. With the
June issue came the promised change and along with it the first in a series of reader
responses. I also found a reader's opinion from the August issue as well. Evidently,
not everyone wanted to honor Heinrich Hertz by naming the base unit of frequency
in his honor...
 "Eventually," Dr. Herwald said, "we believe
it will even be possible to automatically and continuously produce actual electronic
equipment, such as radio receivers and amplifiers, starting from a pool of molten
semiconductor materials." That was in early 1960 in an Electronics World
article titled, "Molecular Electronics." The term "molecular" references what eventually
became integrated circuits (IC), the first of which was realized in 1958 by Texas
Instruments engineer Jack Kilby. Kilby's IC incorporated one transistor, one
capacitor, and three resistors on a germanium substrate. Building on that success,
researchers envisioned single-chip semiconductors which contained hundreds, thousands,
and even millions of transistors, diodes...
 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 models have been added to the product line in June, including
a 9660 MHz (COM1 - COM3) cavity bandpass filter, a 2442 MHz waveguide
band stop filter, and a 2072.5 MHz / 2250 MHz / 1800 MHz triplexer
filter. Custom RF power filter and directional couplers designs can be designed
and produced with required connector...
 I suppose a more appropriate title for this
chart would be "Foreign Valve Substitution Data," considering that most (if not
all) of Europeans refer(red) to vacuum tubes as "valves." As with having posted
scores of Radio Service Data Sheet pages for the benefit of hobbyists who restore
and service vintage radio equipment, I also post other hard-to-find reference resources
when I find them. Sure, the number of people looking for this information is extremely
small, but they are extremely grateful for this when in the throes of finding replacement
tubes (valves). Posting a hyperlink to this page on the RF Cafe homepage will assure
that...
 My father used to refer to the "sweet-voiced
lady predicting the weather over and over again" as my girlfriend because I would
call the "WEather 6-1212" phone number (936-1212) so often. It really wasn't
because I was infatuated with her voice, it's that I was obsessed with weather forecasting.
Most of my free time as a kid and teenager was spent building and flying model airplanes
and rockets, and at eighteen years of age I began taking full-size aeroplane flying
lessons, so my world revolved around a zone extending from terra firma up to about
5,000 feet AGL. This collection of communications news...
 Innovative Power Products has been designing
and manufacturing RF and Microwave passive components since 2005. We use the latest
design tools available to build our baluns, 90-degree couplers, directional couplers,
combiners/dividers, single-ended transformers, resistors, terminations, and custom
products. Applications in military, medical, industrial, and commercial markets
are serviced around the world. Products listed on the website link to detailed mechanical
drawings, electrical specifications, and performance data. If you cannot find a
product that meets your requirements on our website, contact us to speak with one
of our experienced design engineers about your project.
 Welcome to the
RF Cafe Isolators &
Circulators Quiz, an essential assessment for engineers focused on the reliable
sampling and monitoring of signal flow. Directional couplers are the cornerstone
of power metering, reflected power detection, and signal injection in high-frequency
transmission systems. Whether you are calibrating a forward-power monitor, auditing
VSWR in a feedline, or balancing a complex signal distribution network, a rigorous
understanding of coupling factor, directivity, and insertion loss is vital. This
quiz challenges your knowledge of these passive structures, covering the mechanics
of coupled transmission lines, the significance of isolation and directivity, and
the critical trade-offs in power splitters and tap networks. By evaluating your
grasp of these core principles
 Werbel Microwave's
WMADC-0.38-3-40DB-SERIES is a high-power 40 dB directional coupler covering
380 to 3000 MHz, supporting a wide range of VHF, UHF, cellular, LTE, and wireless
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delivers low insertion loss, excellent power handling, and exceptional directivity
for accurate forward and reverse power discrimination. Unlike many broadband couplers
that prioritize ultra-flat coupling, this model is engineered to maximize directivity
across the band, ensuring cleaner separation between forward and reflected signals.
In most real-world systems, coupling variation is easily calibrated out...
 The
medical x-ray machine shown here reminds me of the "Illudium Q-36 Explosive
Space Modulator" contraption Marvin the Martian wanted to use in "Hare-Way to the
Stars" to disintegrate the Earth (because it blocks his view of Venus). Of course
our hero Bugs Bunny thwarts his plan, whereupon Marvin asks, "Where's the kaboom?"
Can you imagine being fraught with cancer and getting strapped into a chair with
that huge hypodermic-needle-looking thingy pointed at you, as shown in this 1959
issue of Popular Electronics magazine? The Caduceus sword in the pic doesn't
help matters, either. The trauma of such an experience might have been worse than
the treatment for some people. As usual the pioneers took the arrows so that we
can benefit from the treatments enjoyed today, and the equipment does not look nearly
as intimidating. See also "After Class: X-Rays" for more info...
 A wee bit of levity in the form of comics
is good for the soul on a busy workday.
Good humor, it is said, contains a degree of truth in it, and this group from
vintage editions of Radio-Craft magazine is no exception. One of the comics
in particular struck a chord with me - the one with the table model radio where
the serviceman is speaking on the phone with his customer. The first familiar feature
is the shape of the radio and the removed rear cover; it reminds me of my Tesslor
R-601S. The second thing is the dead bugs. Just like a stray cat will climb into
your car's engine compartment on a bitter cold day in search of heat, so will
bugs be drawn to a heat source such as that provided by an electronic appliance
filled with warm, glowing vacuum tubes...
Innovative Power Products has been designing
and manufacturing RF and Microwave passive components since 2005. We use the latest
design tools available to build our baluns, 90-degree couplers, directional couplers,
combiners/dividers, single-ended transformers, resistors, terminations, and custom
products. Applications in military, medical, industrial, and commercial markets
are serviced around the world. Products listed on the website link to detailed mechanical
drawings, electrical specifications, and performance data. If you cannot find a
product that meets your requirements on our website, contact us to speak with one
of our experienced design engineers about your project.
 The concept of
exploding wire propulsion is a fascinating relic of the early Space Age concepts,
reflecting an era of high-energy-density experimentation that prioritized power
density over long-term system efficiency. While this 1962 Electronics Illustrated
magazine report captured a valid physical phenomenon - the rapid plasma expansion
of a metallic conductor - the practical implementation for spacecraft encountered
insurmountable engineering hurdles relative to the chemical and electrical propulsion
benchmarks that followed. When you dump several thousand amperes into a 1-mil wire
in nanosecond timescales, you bypass traditional heating...
 Here is another article about a
"prodigal" Ham who returned to amateur radio after about a 30-something year
respite, per this 1955 Popular Electronics magazine. Author Charles Meistroff's
previous experience had been with surplus World War I - yes that's WWI! He must
have been in Heaven to be able to now get his hands on all the new-fangled equipment
now (then) available on the World War II surplus equipment market! I don't know
if the military is still making surplus equipment available like they did even up
through Korea and Vietnam. There must be some great stuff from the Middle East wars
if it is circulating within the surplus market. Then again, other than ruggedness
factors, most commercial equipment is as good or better than MIL-SPEC stuff...
 "If the car is parked in a dark remote spot
it is better to do the job where the car is. This is because auto burglary is a
lesser crime than stealing the whole damn car." That remark was made by a 'former'
thief who ostensibly gave up a life of crime after spending nearly two decades in
the slammer for various infractions of the law. One of his specialties was breaking
into cars to
steal radios - AM, FM, CB, Ham, or whatever was available. Mr. X
volunteered his insight for the benefit of QST readers who might want to take proactive
steps to help minimize the chance of being a victim. The year was 1967, but you
can bet the same mindset pervades the thinking of modern day break and grab thieves
today. Even though most modern portable electronics equipment is protected from
access by passwords, that wouldn't stop a thief from stealing...
 Prior to the emergence of
silicon-based semiconductors, selenium and copper(cuprous)-oxide
rectifiers were the alternatives to vacuum tubes. Copper-oxide (Cu2O)
was popular as a small signal detector since its forward voltage drop was similar
to a Schottky type diode - typically around 0.2 V. Copper-oxide diodes were
used in radios and test equipment meters. Selenium (Se) has a forward voltage drop
of around 1 V, but its high reverse voltage withstanding of 20 V or more
made it popular for voltage rectification, with as many layers as necessary being
stacked serially as required. Selenium rectifier stacks...
 Centric RF is a company offering from stock
various RF and Microwave coaxial
components, including attenuators, adapters, cable assemblies, terminations,
power dividers, and more. We believe in offering high performance parts from stock
at a reasonable cost. Frequency ranges of 0-110 GHz at power levels from 0.5-500
watts are available off the shelf. We have >500,000 RF and Microwave passive
components we can ship you today! We offer Quality Precision Parts, Competitive
Pricing, Easy Shopping, Fast Delivery. We're happy to provide custom parts, such
as custom cables and adapters, to fit your needs. Centric RF is currently seeking
distributors, so please contact us if interested. Visit Centric RF today.
 Welcome to the
RF Cafe Coaxial Cable Quiz,
a technical assessment designed to sharpen your proficiency in the fundamental transmission
media that underpin all radio frequency communications. Whether you are scaling
a tower for antenna installation, troubleshooting impedance mismatches in a feedline
system, or calculating loss budgets for a long-run cable deployment, a firm command
of coaxial theory is vital for maintaining signal integrity and power efficiency.
This quiz challenges your understanding of critical transmission line metrics, including
characteristic impedance calculations, the impact of dielectric constants on velocity
factor, the physics of the skin effect, and the thermal limitations of power handling.
By testing your knowledge...
 If you were hanging around here in 2014,
you might recall a paper I published titled, "Drone-Based Field Measurement System™ (dB-FMS)™." Since that time,
I have seen news items about a few companies using drones to measure antenna radiation
patterns and many more others are coming online all the time. Some amazing working
systems have been implemented that seem to perform very well. I'm not saying
they got the idea from my article because more than one person can have the same
brilliant idea ;-). It's just good to know that my concept had some merit in
the real world...
 My
Vise-Grip pliers have performed a lot of hard duty over the decades.
Many rusted nuts and bolts would still be unremoved if it weren't for their
sharp, corrugated locking jaws. I have 10", 7", and 4" w/cutter, and 6" long nose
models. These are all manufactured under the Petersen Manufacturing Company name,
before they bought Irwin, who now manufactures Vise-Grips. Even high quality tools
eventually show signs of wear after decades of use and abuse. A few of mine had
jaws worn down to the point where they no longer would "bite" into the bolt head
or nut being clamped. I was about to buy a couple new pairs of Vise-Grips, but then
wondered if I could recondition the jaws to put the pointed shape back on the jaws
with a triangle file. Being hardened steel, a lot of times a standard file will
barely scratch the surface, but in this case I managed to dress the jaws of four
pairs of Vise-Grips before the file (double taper triangle) got dull...
 "Stratovision" sounds about as serious as "Wonkavision," but unlike
the candy maker's fictional machine that transported chocolate bars across the
room, Stratovision was in fact a serious proposal. It was an early form of satellite
television. Since orbiting communications satellites would not be practical for
another decade, Westinghouse devised a system in 1945 using aircraft flying at high
altitude to relay television signals. Engineers calculated that 14 airplanes circling
at 25,000 feet could provide coverage to 78% of the country. By 1950 they had a
working system, but needless to say (because nobody has ever heard of it... except
you, now), the concept ultimately did not pan out. It was not because the system
failed to work as designed, but because there was not enough demand...
 Werbel Microwave is a manufacturer of
RF directional and bidirectional couplers (6 dB to 50 dB) and RF power
dividers / combiners (2- to 16-way) with select models operating up to 26.5 GHz
and 100 W of CW power (3 kW peak). All are RoHS and REACH compliant and
are designed and manufactured in our Whippany, NJ, location. Custom products and
private label service available. Please take a couple minutes to visit their website
and see how Werbel Microwave can help you today.
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 Television broadcast stations were quickly
growing in number in the post-Korean War era and the FCC needed to devise a scheme
for
accommodating more channels. There were only 13 channels (only
2-13 used) allocated in the VHF spectrum with 6 MHz-wide bands. Even though
VHF propagates primarily in a line-of-sight mode, reflections and earth-bounce can
extend the range fairly significantly, limiting density in closely spaced cities.
The military refused to yield any spectrum so a decision was made to add new channels
(14-83, also 6 MHz wide) in the UHF band. UHF presented its own problems with
more difficult equipment manufacturing issues and higher atmospheric attenuation.
It never really caught on because cable TV was being widely installed in metro areas...
 Dr. Linder's patented AC and DC
generators exploited alpha (proton) and beta (electron) particle emissions from
radioisotopes contained within. The device is basically a metallic sphere concentric
to an enclosed mounting platform for polonium (α
particle emitter), phosphorous (β particle emitter), or similar elements. With
just a gram of radioactive material, the charge which accumulates on the outer sphere
generates a very high voltage (~1 MV) driving a low current (~1 mA). Georg
Ohm's work tells us that is equivalent to 1 kW of power - quite a lot for
a fairly compact device. Dr. Linder envisioned multiple
atomic generators combined in series and/or parallel to obtain
the required power. No mention was made of the effective internal resistance, which
would ultimately determine the terminal voltage when connected to a load...
 A 720-line HDTV display is made up of 1,280
vertical lines and 720 horizontal lines of pixels, which gives a total of 921,600
pixels. A 1080-line HDTV has 1,920 vertical lines and 1,080 horizontal lines, for
a total of 2,073,600 pixels. In 1969, a 230 vertical line by 230 horizontal line
electroluminescent (EL) flat-screen television display with 52,900
pseudo-pixels was considered a big deal - and it was since it was the starting point
for digital flat-screens of today. Interestingly, while the "pixel" distribution
was square, the actual display retained the standard 4:3 aspect ratio, meaning horizontal
element width was 33% greater than the vertical element. Since each EL element was
addressed individually, there was no ability of a picture element to be shared by
adjacent "pixels," so displaying a circle would result in a very pixelated picture...
 This is a great
electronics-themed comic from a February 1972 issue of Popular
Electronics. It encompasses the essence of the stereotypical salesman ruse,
especially in that era when people were sure that electronics repair services were
out to rip them off by selling unneeded services and replacement parts. Aspiring
TV technicians who couldn't grasp the technology moved on to working as mechanics
in a garage, poking tiny holes in brake lines to scare owners into paying for complete
braking system rebuilds. I usually like to post multiple comics on each page, but
at the moment only this one is available...
 As with your school and college days where once
there was no longer any reason to memorize physical constants, conversion formulas, and
names of people, places, and things, much of the noggin's gray matter was repurposed
to remember topics of more immediate need. You can always look up what you have forgotten.
While studying for your Ham radio or FCC license, being able to be able to quickly convert
between wavelength and frequency is essential. Recalling on demand
frequency-wavelength pairs is a real time saver on a timed exam. Even being able
to perform the conversion on a calculator during the test takes up valuable time that
could be better used on other tasks. This handy-dandy chart for converting...
 Each autumn I used to anxiously await the
appearance of the newest edition of
The Old Farmer's Almanac on the store shelf, and such was the case with this
1981 issue. It is not that I was/am an avid farmer, just that I enjoy reading the
anecdotes, tales, and interesting historical tidbits included amongst the pages
along with tables of high and low tides, moon and sun rising and setting times,
astronomical events, and weather patterns expected for the year that lay ahead.
Most of all, I liked working the puzzles and riddles. Over the years the difficulty
levels gradually got lower and lower (aka dumbed down), to the point where for the
last decade or so I have not even bothered buying the OFA. Now it is full of numbnut
stuff...
 I'm probably one of the few people remaining
who fairly regularly recite the World War II (WWII) era slogan of "Use
it up. Wear it out. Make it do, or Do without." One of the primary killers of
economies has been inflation, whatever the cause - usually deficit spending by government
and/or printing of fiat money. Wartime typically produces high inflation levels
due to the need to produce the equipment necessary to wage a battle. Supply and
demand are another cause of inflation. If the demand is greater than the supply,
prices go up because owners want to maximize profits. If the need for skilled labor
is greater than what is available, workers demand higher pay, and the price goes
up. During WWII, as the chart to the upper left shows, inflation rates were sky
high, and the government propagandists called on the citizens to "do their part"
to keep prices under control by not creating a higher demand then the supply chain
could accommodate...
 Author Howard Wright takes the opportunity
here to distill the
concept of modulation down to its basic operation while dispensing
with the garbled mix of "graphs, formulas, charts, vectors, diagrams, and Greek
letters which often enter into various discussions of modulation". Wright describes
how to the uninitiated radio dial spinner, the culmination of events occurring behind
the scenes in an AM reception is akin to knowing "that, to be reproduced, the picture
[in a magazine] was broken down into its primary colors, if all we had to go by
was the original print and the magazine?" That is a very apt comparison...
-79-
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