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5 of the May 2022 homepage archives. Friday the 27th
 Atomic energy research came to the forefront
of public awareness in 1945 following the detonation of the world's first nuclear
bombs. X-rays had been studied for decades and uses had been developed for medical
and industrial inspection purposes, but the harmful effects of low level exposure
over long periods of time were still largely undetermined. Some people, like the
author of this report from a 1949 edition of Radio & Television News
magazine, believed "man's life is shortened by exposure to any amount of
radioactivity." That was a rather extreme and alarmist statement to make in
an article whose purpose was ostensibly to encourage engineers, scientists, and
technicians to seek careers in the radio-electronics-nucleonics field...
 Power beaming
is one of those things I view as useful for hard to access installations, but very
inefficient for anything other than low power applications. This article in IEEE's
Spectrum magazine provides some insight into the state of the art. "Wires have a
lot going for them when it comes to moving electric power around, but they have
their drawbacks too. Who, after all, hasn't tired of having to plug in and unplug
their phone and other rechargeable gizmos? It's a nuisance. Wires also challenge
electric utilities: These companies must take pains to boost the voltage they apply
to their transmission cables to very high values to avoid dissipating most of the
power along the way. And when it comes to powering public transportation, including
electric trains and trams, wires need to be used in tandem with rolling or sliding
contacts, which are troublesome to maintain, can spark, and in some settings will
generate problematic contaminants. Many people are hungry for solutions to these
issues - witness the widespread adoption over the past decade of wireless charging,
mostly for portable consumer electronics but also for vehicles..."
 Don't let the title fool you. This is not
a "bees-birds-and-flowers
routine" being provided to Barney by his boss, Mac. It turns out to be a brief
introduction into the fine art of troubleshooting intermittent problems in radio
and television circuits. As is usually the case, while the specifics of the scenarios
Mac describes might not apply to your challenge at hand, the general philosophy
always does. It is basically the old process of elimination where after rapping
components mechanically and/or heating or cooling them in hopes of observing a tell-tale
change in performance, the next step is to divide the suspected circuit portion
in half (electrically, but sometimes also physically) and look in one direction.
If the problem isn't there, then divide the circuit in the other direction in half
and go there. Repeat until the problem is found. One of my personal favorite first
steps is to verify all mechanical connector interfaces (if any) are contacting properly.
Clean with alcohol if possible, and burnish with sandpaper if appropriate, then
plug and unplug the connections a few times, just to make sure proper seating...
 Sam Benzacar of Anatech Electronics, an
RF and microwave filter company, has published his May 2022 newsletter that
features his short op-ed entitled "This Will Be the Year That Matter, Matters,"
where he describes how "Matter," which was formerly called Project CHIP (Connected
Home over IP) and then Connectivity Standards Alliance (CSA), was announced in December
2019 with the goal of reducing fragmentation and eliminate interoperability issues
with home automation. As with Wi-Fi and Bluetooth, Matter aims to assure compatibility
between systems and devices of all manufacturers. Also in the news is the ongoing
saga of C-Band cell service and radar altimeter interference, "Smart Agriculture"
revenue projections, and rectenna RF energy harvesting...
 Some of the earliest television display
schemes were mechanically scanned light projection systems rather than electronically
raster scanned cathode ray tubes. This 1930 vintage article from Radio News
magazine reports on a scheme developed by Arthur Watson whereby a specially formed
rotating Monel disk served as the rotating reflecting surface to produce the light
scanning action. This invention was hailed as a breakthrough that would finally
make commercial TV available to the masses.
Mechanical televisions worked by transmitting scanned images of the original
subject in the form of amplitude modulated electrical signals whose voltage was
determined by the level of reflected light. A synchronizing signal was included
in the transmitted data stream. The scan disk on the receiving end rotated at the
same rate as the transmitter scanning disk, and an electric lamp's brightness was
varied according to the signal's picture voltage level...
 With more than 1000
custom-built stencils, this has got to be the most comprehensive set of
Visio Stencils available for RF, analog, and digital system and schematic
drawings! Every stencil symbol has been built to fit proportionally on the included
A-, B-, and C-size drawing page templates (or use your own page if preferred). Components
are provided for system block diagrams, conceptual drawings, schematics, test equipment,
racks (EIA 19", ETSI 21"), and more. Test equipment and racks are built at a 1:1
scale so that measurements can be made directly using Visio built-in dimensioning
objects. Page templates are provided with a preset scale (changeable) for a good
presentation that can incorporate all provided symbols...
 RF Superstore launched in 2017, marking
the return of Murray Pasternack, founder of Pasternack Enterprises, to the RF and
microwave Industry. Pasternack fundamentally changed the way RF components were
sold. Partner Jason Wright manages day-to-day operations, while working closely
with Mr. Pasternack to develop RF Superstore into a world class RF and
microwave
component supplier. RF coaxial connectors & adapters, coaxial cable &
cable assemblies, surge protectors, attenuators. Items added daily. Free shipping
on orders over $25. We're leading the way again!
Thursday the 26th
 That
ultrasonic communications has not proved to be a reasonable means of transmitting
information from one location to another - even over fairly short distances - is
borne out by the obvious lack of such systems today. With all the technology available
in the form of electronics, mechanics, and software, if it were possible to efficiently
and effectively implement systems of ultrasonic communications, such devices would
be as common as the current plethora of wireless systems. Some early research efforts
at ultrasonic communications were published in a 1945 edition of Radio News
magazine. Regardless of the era, the electromagnetic frequency bands are always
deemed to be too crowded so researchers constantly look for other transmission media.
There is one revolutionary new potential form of remote communications on the horizon:
quantum entanglement. Still largely an enigma, entanglement communications exploits
an observed property of some subatomic particles to be inextricably linked to each
other with no discernable medium or known mechanism. Albert Einstein referred to
it as "spooky action at a distance." Don't look for quantum entanglement Internet
routers anytime soon, but once the technology comes to fruition, not only will it
mitigate the need for distribution coaxial and optical cable...
 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.
 This is very cool if you have an interest
in the early developments in television. I have posted many articles from vintage
electronics magazines documents in the
evolution of color TV. This piece entitled "Print an Arduino-Powered Color Mechanical
Television" appeared on the IEEE Spectrum website. It begins: "Before
flat screens, before even cathode-ray tubes, people watched television programs
at home thanks to the Nipkow
disk. Ninety years ago in places like England and Germany, broadcasters transmitted
to commercially produced black-and-white electromechanical television sets, such
as the Baird Televisor, that used these disks to produce moving images. This early
programming established many of the formats we take for granted today, such as variety
shows and outside broadcasts. The size and weight of a Nipkow disk makes a display
with more than a few dozen scan lines impracticable (in stark contrast to modern
screens with thousands of lines). But when a mechanical TV is fed a moving image,
the result is surprisingly watchable..."
 1945 or 2022? Seventy-seven years have passed
since this photo of a
vacuum tube manufacturing facility in China was taken. Given that most new vacuum
tubes are made in China, and that the labor work conditions have not changed much
in the intervening time period (except in high-profile plants like Foxconn where
Apple products are made), this might very likely represent a modern day operation.
BTW, most of the vacuum tubes not being made in China are made in Russia... to assure
their antiquated infrastructure has an ample supple of replacement parts. I say
that only partly in jest. The largest market for new vacuum tubes is music amplifier
equipment and a few commercially made vintage radio replicas (like the Tesslor Model
R601S). BTW, Western Electric (the telephone manufacturer for Bell, back in the
day) is now manufacturing vacuum tubes again...
RF Cascade Workbook is the next phase in the evolution of
RF Cafe's long-running series, RF Cascade Workbook. Chances are you have
never used a spreadsheet quite like this (click here for screen capture). It is a full-featured RF system
cascade parameter and frequency planner that includes filters and mixers for a mere
$45. Built in MS Excel, using RF Cascade Workbook 2018 is a cinch
and the format is entirely customizable. It is significantly easier and faster than
using a multi-thousand dollar simulator when a high level system analysis is all
that is needed. An intro video takes you through the main features...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave
filters, diplexers, and sub-assemblies. They offer the generally known tubular,
LC, cavity, and waveguide designs, as well as state of the art high performance
suspended substrate models. Through a continuous process of research and development,
they have established a full line of filters of filters of all types - lowpass,
highpass, bandpass, bandstop, diplexer, and more. Established in 1979. Please contact
Reactel today to see how they might help your project.
Wednesday the 25th
 The August 1972 issue of Popular Electronics
included a short quiz by William Shippee titled "Test
Your Knowledge of Semiconductors." I guessed wrong on question #2, but guessed
right by process of elimination on question #8 (although afterward I discovered
that in 2012 I had posted an article about the #8 device in Electronics World
magazine). Go ahead and take your best shot. You might be surprised at how much
you've forgotten if you don't work with transistors on a regular basis. I'll bet
Q2 has most people guessing, too...
 "Treating
sub-milliohm chips as a separate class of component is a smart strategy that
helps solve associated design challenges. Part 2 of this series features strategies
for verification of the ohmic value of unmounted components and critical assembly.
The growing use of sub-milliohm chip resistors for current sensing creates a spectrum
of challenges for the designer and the process engineer. The component format should
first be selected to support the chosen thermal-management approach, with metal-element
flat chip resistors having two terminals being the most cost-effective solution.
It's then essential to design the PCB tracks and pads to meet the needs of Kelvin
connection, heat dissipation, and avoidance of induced noise..."
 I signed up as a "Heath Insider" about a
year ago when news first broke about Heathkit's intention to finally, after a couple
decade hiatus, begin producing built-it-yourself electronics kits again. The Explorer Jr.™
is a basic capacitor-tuned AM radio kit that comes complete with everything needed
to build it. Why not a digitally tuned synthesizer with an LCD display? Company
president Andy Cromarty promises many more kits to follow, with all being in the
classic Heathkit tradition of high quality parts and well-written, illustrated,
step-by-step instructions. It will be a continuation of their "You Can Build It.
We won't let you fail." motto. Since originally posting this page in 2015, Heathkit
has been making slow but steady progress with expanding their line of build-it-yourself
projects. They also now have a cool T-shirt design showing an exploded view of their
"Most Reliable Clock™" model GC-1006, with the proclamation "Heathkit's
Back. It's About Time."
 The ARRL (American Radio Relay League) might
be considered as one of the first app developers. At 50¢ and $1 per app, the price
was in-line with one of today's typical not-for-free Apple or Android app. A user
willing to shell out $4 for all six had at his fingertips calculators and reference
tables for capacitive and inductive reactance, resonant frequency, gain and power,
conductor amperage, transformer turns ratio, resistor, capacitor, and inductor series
and parallel combination, and other values. These six apps, dubbed "Lightning Calculators,"
were comprised of bit of cardboard, plastic, and a metal eyelet, not data bits.
Here is a for-real Type B "Lightning Calculator," graciously provided by Joseph
Birsa, N3TTE...
 Repair service businesses have always gotten
a bad rap for deliberately inflating part and labor costs - often deservingly so
- but it's a shame the honest brokers are dragged down by the scum (or "gyps" as
this article calls them). Come to think of it, the word "gyp" is likely short for
"gypsy," which is sure to offend someone these days. Along with admonishing customers
to beware of shyster servicemen, there is an example of an orchestrated "sting"
operation whereby a radio set was intentionally "broken" in a certain way with witnesses
as to the fault, and then a couple dozen repair services were called upon to troubleshoot
and fix it, then present a bill for their work. The result is interesting, and even
resulted in one guy being prosecuted. The story reminds me of a similar much-publicized
sting that was done back in the 1990s against car repair services that were creating
leaks in brake lines and then charging customers to fix them...
 New Scheme rotates
all Banners in all locations on the page! RF Cafe typically receives 8,000-15,000
website visits each weekday.
RF Cafe is a favorite
of engineers, technicians, hobbyists, and students all over the world. With more
than 12,000 pages in the Google search index, RF Cafe returns in favorable
positions on many types of key searches, both for text and images. New content is
added on a daily basis, which keeps the major search engines interested enough to
spider it multiple times each day. Items added on the homepage often can be found
in a Google search within a few hours of being posted. I also re-broadcast homepage
items on LinkedIn. If you need your company news to be seen, RF Cafe is the
place to be.
 Aegis Power Systems is a leading supplier
of AC-DC and
DC-DC power supplies for custom and special applications. Aegis has been designing
and building highly reliable custom power supplies since 1995. They offer a complete
line of switch mode power supplies and power converters for a variety of markets
including defense, industrial, aircraft, VME, and telecom. Supports military, aircraft,
EV, telecom, and embedded computing applications. Design and manufacture of custom
power supply solutions to meet each customer's exacting specifications. Please visit
Aegis Power Systems today.
Tuesday the 24th
 This 1954 issue of Radio-Electronics
magazine reported on the death of electronics communications pioneer
Major Edwin H. Armstrong. Most famously known for his wideband FM (frequency
modulation) scheme, Maj. Armstrong also developed the superheterodyne circuit,
the superregenerative circuit, and was an independent inventor of regeneration.
As with many prodigious, prolific inventors throughout the ages, he spent much time
and fortune battling legal claims against himself and against others. Interestingly,
the news item does not mention that Major Armstrong, who was famous for his daring
antics at the tops of extremely high antennas, died after jumping out of his New
York City apartment window. It was ruled a suicide based on a note he left for his
wife. Also included is a bit about a judge allowing radar data from police as evidence
in a speeding charge, and a statistic showing 47,000 people injured themselves in
the past year during TV antenna installations...
 Augustin-Jean Fresnel, the same guy who
developed the "Fresnel
zone" equation for determining the effective RF propagation region between a
transmitter and a receiver, also invented this prismatic lens for concentrating
the source of illumination of a lighthouse in the direction most useful to seafaring
vessels (aka ships and boats). This IEEE Spectrum article entitled "Before Ships Used GPS, There
was the Fresnel Lens" dives into the history of the world-changing device. It
begins: "Ships today use satellite-based radio navigation, GPS, and other tools
to prevent accidents. But back at the beginning of the 19th century, lighthouses
guided ships away from rocky shores using an oil lamp placed between a concave mirror
and a glass lens to produce a beam of light. The mirrors were not very effective,
though, and the lenses were murky. The light was difficult to see from a distance
on a clear night, let alone in heavy fog or a storm..." Here is a nice
video explaining the Fresnel
lens and its nautical import.
 Here is
Zenith Models 5D011-5D027 schematic and parts list as featured in a 1947 edition
of Radio News magazine. Unlike with most of the Radio Service Data Sheets,
this came from group of three which also included the Bendix Models 636A, C, D and
the Coronet Model C-2, al three of which are tabletop models. As mentioned many
times in the past, I post these online for the benefit of hobbyists looking for
information to assist in repairing or restoring vintage communication equipment...
 Planar Monolithic Industries (PMI), a leading
supplier of custom, high-reliability MIC/MMIC components and subsystems for applications
in space, military, communications, commercial and consumer electronics systems
for more than three decades, announces a dba (doing business as) name change
to Quantic PMI. They also have introduced a new 6-Channel Switch Filter
Bank that operates over the frequency range of 55 to 18.5 GHz, with a typical
VSWR of 1.7:1, a maximum switching speed of 200 ns, and a typical insertion
loss of 4.0 dB. Contact PMI today for more information...
 These two
electronics-themed comics appeared in a 1952 edition of Radio &
Television News magazine. In the early days of television, it was common in
comedy skits and in cartoons to have someone on a television show interact, to the
viewer's great shock, directly with the viewer or to reach out of the set and do
something, as in the first comic here. The Three Stooges show did that in a couple
shows. One in particular I remember was when they were doing plumbing in a house
and had water coming out of light sockets and telephones. The homeowners were watching
the TV with a film of Niagara Falls when suddenly water came gushing out of the
picture tube (begins at 13:20 in video)...
 This assortment of custom-designed themes
by RF Cafe includes T-Shirts, Mouse Pads, Clocks, Tote Bags, Coffee Mugs and Steins,
Purses, Sweatshirts, and Baseball Caps. Choose from amazingly clever "We Are the World's
Matchmakers" Smith chart design or the "Engineer's Troubleshooting Flow Chart."
My "Matchmaker's" design has been ripped off by other people and used on their products,
so please be sure to purchase only official RF Cafe gear. My markup is only a paltry
50¢ per item - Cafe Press gets the rest of your purchase price. These would make
excellent gifts for husbands, wives, kids, significant others, and for handing out
at company events or as rewards for excellent service. It's a great way to help
support RF Cafe. Thanks...
 Berkeley Nucleonics Corporation (BNC) is
a leading manufacturer of precision electronic instrumentation for test, measurement,
and nuclear research. Founded in 1963, BNC initially developed custom pulse generators.
We became known for meeting the most stringent requirements for high precision and
stability, and for producing instruments of unsurpassed reliability and performance.
We continue to maintain a leadership position as a developer of custom pulse, signal,
light, and function generators. Our designs incorporate the latest innovations in
software and hardware engineering, surface mount production, and automated testing
procedures.
Monday the 23rd
 Both my father and grandfather were
stamp collectors - philatelists is the technical word - who dabbled in a recreational
way with commemoratives from foreign countries. Nearly all were canceled (used)
stamps that today, as back in their day, have no real value other than to someone
interested in history. Of course none are the rare types. I now possess many of
those stamps in an album that was painstakingly hand-illustrated and assembled to
arrange each stamp according to its country and issue date. At one time I, too,
dabbled in the hobby, having collected many plate blocks and special issue U.S.
stamps in the 1970s and 1980s, along with purchasing a few designs of special purpose
such as those with aerospace and communications themes. Sad to say, most of those
stamps, even those in mint condition, are valued at the denomination printed on
the face - meaning inflation has reduced their worth to even less than when originally
purchased. If indeed "what's past is prologue...
 This story entitled "Universal
Access Akin to the Electrification of Rural America" is right from the standpoint
of making Internet available in nearly every region of the country. However, there's
one huge difference between the
Internet for All (IFA) scheme and the
Rural Electrification
Act (REA) of 1936. Whereas he REA made electric power available to users, the
end user paid for energy consumed. The IFA either gives away the data usage or provides
deep discounts, while those of us who pay full price for service and pay income
taxes foot the bill - while being demonized by the government and the (often) freeloaders.
Also, the REA did not provide the implements which would benefit from the electric
power (motors, radios, refrigerators), but the government will be handing out cellphones
and PCs to connect to the Internet. Whether through direct taxes or inflation due
to money printing, the rest of us pay dearly for it. The article begins: "Step by
step the $1T infrastructure package is becoming reality The next phase of the U.S.
"Internet for All" initiative has kicked off with governors and other eligible leaders
being invited to submit a letter of intent as a step towards unlocking $45B to give
every U.S. resident access to high-speed internet by 2028. Each state will then
get $5M..."
 My first thought when seeing the cover for
this December 1936 edition of Radio-Craft magazine was that it was an April
Fools gag, but it turns out the
"Hat" being worn by the radio receiver's designer is a loop antenna for AM reception.
In a way it is the opposite of a tinfoil hat in that this headgear invites electromagnetic
energy around the wearer's head rather than shielding it. Back in 1936, being seen
in public donning a contraption like this radio would have been akin to wearing
Google Glass (a failed concept) a few years ago - you'd be a superhero to fellow
nerds, and just be confirming your otherworldly nerd status to non-nerds. Note the
very nicely done drawings...
 RF Cafe's raison d'être is and
always has been to provide useful, quality content for engineers, technicians,
engineering managers, students, and hobbyists. Part of that mission is offering
to post applicable job openings. HR department employees and/or managers of
hiring companies are welcome to submit opportunities for posting at no charge
(of course a gratuity will be graciously accepted). 3rd party recruiters and
temp agencies are not included so as to assure a high quality of listings.
Please read through the easy procedure to benefit from RF Cafe's high quality
visitors ...
 ASC designs and manufactures hybrid, surface
mount flange, open carrier and connectorized amplifiers for low, medium and high
power applications using gallium nitride (GaN), gallium arsenide (GaAs) and silicon
(Si) transistor technologies. ASC's thick film designs operate in the frequency
range of 300 kHz to 6 GHz. ASC offers thin film designs that operate up
to 20 GHz.
Sunday the 22nd
 This custom made
Analog Engineering theme crossword puzzle for May 22nd is provided compliments
of RF Cafe. All RF Cafe crossword puzzles are custom made by me, Kirt
Blattenberger, and have only words and clues related to RF, microwave, and mm-wave
engineering, optics, mathematics, chemistry, physics, and other technical subjects.
As always, this crossword puzzle contains no names of politicians, mountain ranges,
exotic foods or plants, movie stars, or anything of the sort unless it/he/she is
related to this puzzle's technology theme (e.g., Reginald Denny or the Tunguska
event in Siberia). The technically inclined cruciverbalists amongst us will appreciate
the effort. Enjoy!
 With more than 1000
custom-built symbols, this has got to be the most comprehensive set of
Visio Symbols available for RF, analog, and digital system and schematic
drawings! Every object has been built to fit proportionally on the provided
A-, B- and C-size drawing page templates (or can use your own). Symbols are provided
for equipment racks and test equipment, system block diagrams, conceptual drawings,
and schematics. Unlike previous versions, these are NOT Stencils, but instead are
all contained on tabbed pages within a single Visio document. That puts everything
in front of you in its full glory. Just copy and paste what you need on your drawing.
The file format is XML so everything plays nicely with Visio 2013 and later...
 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.
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
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