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5 of the December 2020 homepage
archives. Monday 28
 Sometimes I post advertisements such as this
one for vintage test equipment from a 1938 issue of Radio News magazine
just so people can see how much things have changed, and how good we have it with
today's compact, highly functional products. These
Superior Instrument Company multimeters, signal generators and vacuum tube testers
were truly superior instruments considering the materials and methods available
at the time. Chassis were made from sturdy wood or metal (not much plastic then),
and the finishes were often of very attractive stain and varnish, fabric lamination,
paint, or a combination thereof. Price-wise, the Model 1110-S A.C. - D.C Volt Ohm
Milliammeter price tag of $7.95 in 1938 is the equivalent of $147.77 in today's
money, which is not unreasonable for a superior instrument...
 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!
 Mr. Wilfred Jensby wrote an incredibly detailed
article for the November 1966 edition of QST that delves deeply into the
subject of using
transmission lines as distributed circuit elements. I did a search on his name,
figuring that he likely had other publications of like sort, but nothing was found.
Information contained herein is similar to what you would expect to find in a Master's
level engineering course textbook or in a $100+ technical book from Artech House,
Cambridge University Press, John Wiley & Sons, etc. The brain-zapping equations
are omitted with only a great, layman-level discussion of the concepts and some
really nice illustrations and graphs. This is definitely an article you will want
to check out and pass on to colleagues...
 Exodus Advanced Communications' AMP2071A-LC,
80 to 1000 MHz, 750 Watts with our Quiet-Cool Technology Exodus AMP2071A-LC
is a powerhouse in a compact chassis! Covering 80-1000 MHz, produces >750 W
minimum, >1100 W nominal power, P1dB >500 W minimum. Excellent gain
flatness with a minimum power gain of 58 dB. Included are amplifier monitoring
parameters for forward / reflected power, VSWR, as well as voltage, current &
temperature sensing for optimum reliability & ruggedness. Nominal weight is <40 kg,
and dimensions of 19"W x 22"L x 8.75"H. Features Class A/AB linear LDMOS design
Instantaneous ultra-wide bandwidth Rack mounted system Designed for broadband EMI/RFI,
Lab, Communications and EW applications Suitable for all single channel modulation
standards Built-in protection circuits...
 Vintage radio fans will be interested in
this news article entitled, "NASA
scientists design a nanoscale complementary vacuum field emission transistor."
"Jin-Woo Han is Senior Scientist at NASA's Ames Research Center in California's
Silicon Valley. Along with colleagues Meyya Meyyappan, Myeong-Lok Seol and Jungsik
Kim, he has designed a nanoscale complementary vacuum field emission transistor
(VFET). A vacuum field emission transistor (VFET), also known as nanoscale vacuum
channel transistor, is a device with no semiconductor channel. Instead, it has an
empty gap between the source and drain terminals. Electrons tunnel through this
empty space. Vacuum diodes and triodes have long been known and used in numerous
applications. Recently, researchers have combined the best of vacuum physics and
modern integrated circuit manufacturing to produce VFETs on wafer scale with extremely
small dimensions..."
 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!
Sunday 27
 This December 27th crossword puzzle has many
words
and clues related to Filters (indicated with an asterisk *). For the sake
of avid cruciverbalists amongst us, each week I create a new crossword puzzle that
has a theme related to engineering, mathematics, chemistry, physics, and other technical
words. As always, this one 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., Hedy Lamarr or the Bikini Atoll). The technically
inclined cruciverbalists amongst us will appreciate the effort. Enjoy!
Friday 25
 "Researchers
at Hewlett Packard Labs, where the first practical memristor was created, have invented
a new variation on the device - a
memristor laser. It's a laser that can have its wavelength electronically shifted
and, uniquely, hold that adjustment even if the power is turned off. At the IEEE
International Electron Device Meeting the researchers suggest that, in addition
to simplifying photonic transceivers for data transmission between processors, the
new devices could form the components of superefficient brain-inspired photonic
circuits. Different colors of light can travel simultaneously through optical fibers
and other waveguides so photonic transceivers that can adjust their wavelength..."
 "A DARPA network technology program recently
concluded field tests demonstrating novel software that bridges
multiple disparate radio
networks to enable communication between incompatible tactical radio data links
- even in the presence of hostile jamming. The technology is transitioning to Naval
Air Systems Command (NAVAIR) and the Marine Corps, which plans to put the software
on a software reprogrammable multi-channel radio platform for use on aircraft and
ground vehicles. Started in 2016, the Dynamic Network Adaptation for Mission Optimization
program, or DyNAMO, has developed technologies that enable automated, real-time
dynamic configuration of tactical networks to ensure that heterogeneous radio nodes..."
 Game playing with a remote opponent is routine
these days thanks to the Internet, but a couple decades ago it was not quite so
easy. A checkers
or chess match via telephone, snail mail (the only kind of mail at the time), or
even fax machine were the venues available to the common man, but Hams had another
means - radio! Using either Morse code or voice (aka phone) and a playing board
set up like the one shown in this article, two players could easily match wits anywhere
in the world where signals could be exchanged. Evidently the participants could
get so wrapped up in the game that they risked forgetting to broadcast their call
signs at the legally required interval (every 10 minutes), so author Utterback provides
a friendly admonition at the end...
Reactel has become one of the industry leaders in the design and manufacture
of RF and microwave filters,
diplexers, and sub-assemblies. They offer the generally known tubular, LC, cavity,
and waveguide designs, as well as state of the art high performance suspended substrate
models. Through a continuous process of research and development, they have established
a full line of filters of filters of all types - lowpass, highpass, bandpass, bandstop,
diplexer, and more. Established in 1979. Please contact Reactel today to see how
they might help your project.
Thursday 24
 Here are a few of my favorite
Christmas music
videos. They include an eclectic mix of Cloverton, the Trans-Siberian Orchestra,
an unlikely duet sung by Bing Crosby and David Bowie, and Casting Crowns. Watching
the instruments being played really enhances the effect of the song. I used to have
the videos embedded in this page for easy viewing all in one place, but each year
on some of them I have to go find new hosting location because the previous year's
had been removed. This time I am just linking to the YouTube (and other) web pages.
The U.S. Air Force Band performance at the Smithsonian Air and Space Museum is my
newest addition for 2020...
 Some of the best electronics-themed comics
appearing in these vintage magazines are the "Radio
Term Illustrated" type - IMHO, anyway. Most of them are ideas suggested by readers,
then illustrators like Frank Beaven created the visuals. The comic on page 79 is
pretty self-explanatory, but the page 66 pun might need some explanation to those
unfamiliar with vacuum tube circuits. The "B" battery is a term created by Mr. Lee
de Forest as a designation for the second battery required for the plate bias
(the "B") of his Audio tube. Typical voltages were 45 volts, 67½ volts, and 90 volts.
If that doesn't completely clear up the pun, then you also need to know that an
alternative definition of battery which is a military artillery installation...
 "Radar has become a mainstay for
advanced driver-assistance systems (ADAS), and the single radar used for advanced
cruise control is being augmented by half a dozen or more radar systems. By 2023,
cars will have a mix of radar, lidar, and camera-based systems providing significantly
more situational awareness to the driver, in addition to being used by self-driving
car solutions. By 2023, more than half of new vehicles will incorporate radar as
well as other long-range sensor systems. NXP Semiconductors has been a major supplier
of radar technology for automotive applications. Its latest offering starts off
with the TEF82xx radar transceiver. A single chip can address a number of applications
supporting 76- to 81-GHz bands with usable bandwidths up to 4 GHz. A 6-bit phase
rotator enables advanced modulation MIMO and beam-steering support..."
 The December 1958 (my 1st Christmas) issue
of Radio-Electronics magazine featured a clever take-off of the famous
children's story "Twas the Night Before Christmas," by Clement Clarke Moore (originally
titled A Visit from St. Nicholas). "The
Day Before Christmas," by Jack Darr, might contain some terms not familiar to
a more contemporary crowd. For instance, how many even know that "Gunsmoke" was
a Prime Time television shown from the 1950's, and is not just a forbidden word
in today's public schools (since it contains the word "gun")? How about an antenna
on the roof, or a telephone with a "dial" on it? Most people don't even carry paper
"pelf" around anymore. If you're under 30 years old and run across an unfamiliar
word or phase, simply speak it into your smartphone and Siri (or some variant) will
be glad to look it up for you ;-) ...
 As our traditions are besieged by malcontents
determined to denigrate, impugn, and ultimately erase memories of holidays and events
that have meant so much to families and friends, I feel compelled to resist the
movement by documenting parts of the past that will cause us to wax nostalgic over
our cherished traditions. Intimidation and violence is part of the strategic calculus;
we have seen it in spades in 2020, and 2021 promises to be even worse. The Cancel
Culture might eventually win out with the complicity of government agents both elected
and unelected, but I'm not going down without a fight. Here is a collection of twentieth
century, December issue
QST magazine
covers with Christmas themes that will no doubt be familiar to many of you.
Finding them was more difficult...
 Withwave manufactures an extensive line of
metrology quality coaxial test cable assemblies, connectors (wave-, end-, vertical-launch,
board edge, panel mount), calibration kits (SOLT), a
fully automated 4-port vector
network analyzer (VNA) calibrator, between- and in-series connector adaptors,
attenuators, terminations, DC blocks, torque wrenches, test probes & probe positioner.
Special test fixtures for calibration and multicoax cable assemblies. Frequency
ranges from DC through 110 GHz. Please contact Withwave today to see how they
can help your project succeed.
 Whenever I see advertisements for electronics
training courses, I think of the line in "Duel in the Snow, or, Red Ryder Nails
the Cleveland Street Kid," where it mentions how during the Great Depression years
the magazines were filled with ads "promising successful careers repairing radios."
That story, which ultimately became the book and movie "A
Christmas Story," was contained in Gene Shepherd's book In God We Trust: All
Others Pay Cash. Jean Shepherd was a radio announcer and story teller who first
read "A Christmas Story," on his WOR (New York City) show in 1970. You can listen
to a 1974 broadcast in the YouTube video embedded below. This reading is slightly
different than the one given to me by a guy who actually recorded it on tape...
 Electro-Photonics is a global supplier of
RF & Microwave components.
Their products include SMT hybrid and directional couplers, wire bondable passive
components, mounting tabs, filters, transmission lines, and very useful test boards
for evaluating components (spiral inductors, single-layer capacitors). The Electro-Photonics
team can support your small R&D design requirements with RF & Microwave
test fixtures and save you valuable design and characterization time. Please take
a moment to visit Electro-Photonics' website and see how your project might benefit.
Wednesday 23
 Probably the biggest news in the March 1944
issue of Radio-Craft magazine's "Monthly Review" feature was the invention
of an extremely sensitive particle mass analyzer by Dr. James Hillier, of Radio
Corporation of America (RCA). Vladimir Zworykin, who you might recognize as a television
pioneer, is in the photo with Dr. Hillier. A related technology, electron microscopy,
was used to image viruses in the blood stream. The National Bureau of Standards,
now called NIST, announced a new
time standard broadcast signal consisting of a precise 2.5 MHz pulsed tone
feature a missing pulse once per minute. This facilitated calibration of frequency
and time standards. There is also an analog simulator built by Westinghouse for
use in designing high voltage power transmission networks where up to 18 separate...
 "Loon LLC, an Alphabet Inc. subsidiary, is
working to bring HAPS-powered Internet access to unserved and underserved communities
around the world. Loon has submitted its statement pursuant to the US Federal Communications
Commission (FCC) in support of its application for an Experimental Radio Service
License to conduct a market trial. Loon seeks authority to tap spectrum between
70 GHz and 90 GHz (E-band), from fixed base stations in Puerto Rico that will
utilize High Altitude Platform Stations (HAPS) as relay transmission points to deliver
broadband service to maritime vessels operating in line-of-sight..."
 "Nothing is ever a complete failure; it can
always serve as a bad example." - Carson's Consolation. I tried to find out who
this Carson guy is, but to no avail. It is probably not John Renshaw Carson, who
developed the well-known amongst RF Cafe visitors
bandwidth rule
stating BW = 2·(Δf + fm). The same quote is sometimes
referred to as Carlson's Consolation. Regardless of its progenitor, the tenet holds
true.
 Axiom Test Equipment allows you to
rent
or buy
test equipment, repair
test equipment, or
sell or trade test equipment. They are committed to providing superior customer
service and high quality electronic test equipment. Axiom offers customers several
practical, efficient, and cost effective solutions for their projects' TE needs
and is committed to providing superior customer service and high quality electronic
test equipment. For anyone seeking a way to offload surplus or obsolete equipment,
they offer a trade-in program or they will buy the equipment from you. Some vintage
items are available fully calibrated. Please check out Axiom Test Equipment today!
 After seeing
the
Future Radio Rockets article I posted recently, website visitor and contributor
Joseph Birsa (N3TTE) sent me a note about the vintage "Rocket Radio" toy that was
around when he (and I) were kids. The CrystalRadio.net website has a great page
devoted to the Rocket Radio,
including a schematic and theory discussion. It used a single crystal - a 1N34 diode
- for the detector and a simple LC tank circuit for tuning. An ear bud (as opposed
to a speaker) provided the audio signal since being entirely passive, the signal
power from the ether to the ear bud had to be provided entirely by the radio wave
- which is pretty amazing when you think on it. Conspiratorialist tweak: If the
EM wave can provide enough power (after detection) to stimulate your eardrum, can
it also stimulate your brain directly as a radio wave? As is usual, you can probably
get a vintage Radio Rocket on
eBay if you're willing to pay the super high price most of these items are commanding
these days.
 As was customary for U.S. businesses,
Hallicrafters
ran a Christmas advertisement in the January issue of magazines where they appeared.
The January edition, as is common even now, is typically mailed in early December,
getting it in the hands of readers in time for Christmas. This "Here's to a Good
Old Fashioned Christmas" (which many state governors want to end beginning this
year) message appeared in the January 1942 issue of QST magazine. Halli(gan) and
(hand)crafters was founded in Chicago in 1932 by William J. Halligan. The company
designed and manufactured radio equipment for hobby, commercial, and military applications
and quickly became very popular amongst their users...
 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 22
 In spite of the benefit afforded by the well-respected
accuracy of the
Norden bomb sight, striking a target from altitudes of up to thirty thousand
feet is literally a hit-or-miss prospect. At that distance, a small angular error
in the sighting mechanism can equate to hundreds of feet at ground level. A one
degree field of view from 30,000 feet covers a ±262 foot area, which is good enough
for dropping a huge barrage of bombs on a munitions factory spread out over a few
hundred acres. However, the higher the aircraft flies, the more variables enter
the calculation on the bomb's earthward trajectory. Wind shears and aircraft altitude,
ground speed, and direction needed to be accounted for, all of which was calculated
automatically by the Norden's analog computer...
 "On the electromagnetic spectrum, terahertz
light is located between infrared radiation and microwaves. It holds enormous potential
for tomorrow's technologies: Among other things, it might succeed 5G by enabling
extremely fast mobile communications connections and wireless networks. The bottleneck
in the transition from
gigahertz to
terahertz frequencies has been caused by insufficiently efficient sources and
converters. A German-Spanish research team with the participation of the Helmholtz-Zentrum
Dresden-Rossendorf (HZDR) has now developed a material system to generate terahertz
pulses much more effectively than before. It is based on graphene..."
 Sam Benzacar of Anatech Electronics, an RF
and microwave filter company, has published his December newsletter that features
his short op-ed entitled "2020:
The Year that Was... ," in which Sam assess how he well did in predicting various
key industry trends at the end of last year. You can read his piece to see how he
scored, but I do want to note a specific point. One of Sam's predictions pertained
to the availability of broadband service in rural areas. The Wuhan Flu epidemic
that caused most schools to implement a remote classroom environment exposed how
deficient the system still is, even though we thought the issue had been pretty
much resolved (goodness knows we've spent enough tax money to address it). Also
included in the newsletter are a few pertinent industry headlines. Stand by for
Sam's end-of-year predictions for 2021...
 Triad RF Systems designs and manufactures
RF power amplifiers and systems.
Triad RF Systems comprises three partners (hence 'Triad')
with over 40 years of accumulated knowledge of what is required to design, manufacture,
market, sell and service RF/Microwave amplifiers and amplifier systems. PA, LNA,
bi-directional, and frequency translating amplifiers are available, in formats including
tower mount, benchtop, rack mount, and chassis mount. "We view Triad more as a technology
partner than a vendor for our line-of-sight communications product line." Please
check to see how they can help your project.
 I saved this poem from the December 1935
edition of the ARRL's QST magazine for now since it might be the last day
of work for the year for many people. "The Day
Before Christmas" was penned by radio amateur Robert H. Votaw after the manner
of the classic "The Night Before Christmas." It is rare to see such a poem printed
in a technical magazine these days, but it was fairly common back in the day. To
wit: "Ravin" (1942), "Power Supply" (1944), "Pre-Radio" (1944), "A Radioman's Nightmare"
(1945). If you happen to be related to or knew Mr. Votaw, please send me a note...
 An
RF Cafe visitor sent this equation to me a few years ago. It can be found all over
the Internet (including here), but I cannot determine a definite origin. Mathematicians
claim that math can explain everything in the universe, which is not quite true.
It can't for example, explain why my next-door neighbor is a junk hoarder. This Christmas equation does not
appear to begin with a particular application; it looks like something from a set
of textbook end-of-chapter problems. Even if you don't celebrate Christmas, it provides
a secondary benefit by demonstrating rules for the manipulation of logarithms and
exponents along with basic algebraic rearrangements of terms.
 NorthEast RF's comprehensive
antenna testing
services include linear | circular polarized antenna measurements and OTA cellular
device pre-compliance. Up to 18" diameter and <10 kg weight. Antennas can be
rapidly evaluated and optimized using our fast near field spherical system. Test
results supplied in data file with pattern viewer software. A picture of the test
configuration is included to help aligned axis. Our selection of human head and
hand phantoms are ideal for verification of body worn devices. Turnaround time is
usually 3-days.
These archive pages are provided in order to make it easier for you to find items
that you remember seeing on the RF Cafe homepage. Of course probably the easiest
way to find anything on the website is to use the "Search
RF Cafe" box at the top of every page.
About RF Cafe.
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- Christmas-themed
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