RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
2 MB. Its primary purpose was to provide me with ready access to commonly needed
formulas and reference material while performing my work as an RF system and circuit
design engineer. The World Wide Web (Internet) was largely an unknown entity at
the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps
while tying up your telephone line, and a nice lady's voice announced "You've Got
Mail" when a new message arrived...
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See Page 1 |
4 of the November 2018 homepage archives.
Veterans Day 2018: A Pittance of Time
This is my annual Veterans
Day tribute. On November 11 (the 11th day of the 11th month), at 11:00 am (the 11th
hour), we observe 2 minutes of silence in honor of countrymen who "gave the last full measure of devotion." A Pittance of Time
is performed by Canadian citizen Terry Kelly
(he went blind at an early age). It was written after an experience he had on
Veterans Day in 1999. It is done in the finest Celtic tradition.
Yes, I needed to look up the definition of "callithump."
I have to admit to not really being sure why the title seemed apt to the editors. This
is two separate mini-stories. The first, "A Dubious Tale," is a clever manipulation of
a very familiar electronics / electrical mathematical law applied to a fictional town
located on the shores of Scandinavia. The second, set in the mid-1960s, tells a futuristic
tale - projected way forward into the 1980s - of a discussion between a father and his
son regarding how things are going at school. Unlike similar predictions in the 1960s
of a flying car in every garage and Dick Tracey watches on every wrist, this scenario
has, although not exactly as envisioned, come to fruition ...
ISCAD - Electrical Drive with 0% Rare Earths,
25% Higher Driving Range
Motor technology is advancing by leaps and bounds,
as is battery technology. Power and energy density is incredibly high compared to a mere
two decades ago. Check this out. "Conventional electrical machines do face the problem
that due to their fixed windings the number of pole pairs cannot be changed. Electrical
machines are thus low-loss energy converters only for an optimized operating point. Apart
from that point, the efficiencies of conventional electric drives are decreasing enormously.
ISCAD system, instead of copper windings, aluminum bars are used
in the stator. Every single bar is supplied by a dedicated power electronics ..."
Triad RF Systems 2018 Q4 Newsletter Is Here
Triad RF Systems has published their 4th quarter
newsletter for 2018. In addition to presenting new RF amplifier products for CubeSats,
defense, and aerospace applications, they are proud to announce their inclusion in the
list of companies - #2839 to be exact, which is quite an accomplishment given the millions
of companies out there. Also, Mr. Patrick Sherlock is the new VP of Business Development
at Triad RF Systems. Sounds to me like a lot of good news from Triad RF Systems ...
Squires Sanders CB's Advertisement re Sporadic E
Sporadic E skip is an upper atmosphere phenomenon
whereby the "E" layer is ionized to where certain radio frequency (RF) wavelengths are
refracted to the degree that they are bent back down towards the earth's surface rather
than exiting into space. It facilitates long distance (DX) communications to areas not
normally available otherwise. Amateur radio operators (Hams) have exploited sporadic E
skip for nearly as long as there has been Ham operators - even before anyone knew for
certain that the upper atmosphere could be ionized. Thus far there is no concrete correlation
between sunspot activity and sporadic E propagation, although sunspots definitely
have other profound effects on propagation when highly energetic electrons released from
the sun's ...
GE Model M-49 Radio-Phonograph Restoration by Jeff B.
RF Cafe visitor Jeff B. of Beverly, MA, sent
me these photos of his
General Electric Model M-49, 4-tube radio-phonograph, dual-wave superheterodyne set
that he is going to restore to working order. It appears to be in extremely nice condition
for a 1930s era unit. He found the Radio Service Data Sheet from a January 1935 issue
Radio-Craft magazine that I posted back in October 2016. These are now the only
images of the M-49 anywhere I can find on the Internet ...
RF Superstore: Supplier of RF & Microwave
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
component supplier. RF coaxial connectors & adapters, coaxial cable & cable
assemblies, surge protectors, attenuators. Items added daily. Free shipping on orders
over $99. We're leading the way again!
Navy Destroys Ballistic Missile Target
in Successful Interceptor Test
"U.S. sailors aboard the Arleigh Burke-class destroyer
John Finn destroyed a target Friday with the latest version of the Standard Missile-3
interceptor during a flight test off the coast of Hawaii. The ship launched the
SM-3 Block IIA guided missile, which then successfully intercepted
a medium-range ballistic missile target deployed from the Pacific Missile Range Facility
at Kauai, Hawaii, according to a U.S. Missile Defense Agency press release. Mark Wright,
a spokesman for MDA, confirmed that the SM-3 Block IIA impacted with the target. 'It's
a kinetic kill vehicle, meaning it has to slam into the target, not just explode near
it,' he told Military.com ..."
VDR's and Thermistors
Pop Quiz: What is the contemporary name we have
given to the
voltage variable resistor (VDR)? Although VDRs are nowadays used most familiarly
for overvoltage protection due to spikes on a power or signal line, they used to be functional
parts of television display and power supply circuits. They also made those newfangled
field effect transistors - junction (JFET), and enhancement mode and depletion mode insulated-gate
(IGFET, aka MOSFET). Thermistors, silicon-controlled rectifiers (SCRs), and varactor
diodes are also discussed. Sylvania was a prime user of all these devices back in the
day as part of their effort to modernize televisions and radio by abandoning vacuum tubes
wherever possible ...
'Invisible Glass' Takes First Prize in
'Create the Future' Contest
Impedance matching between two transmission mediums
(media?) is essential to maximum power transfer from one to the other. Imperfect impedance
matching results in reflections of the incident signal, thereby reducing the amount of
signal transferred to the other medium. We in the RF realm are accustomed to the phenomenon
of voltage standing ratio (VSWR), but in the world of optics and mechanics, similar impedance
mismatch issues are important. This article in NASA's Tech Briefs reports on 'invisible glass' that is rendered so via nanoetching techniques on
the surface instead of the typical thin film polymers. Doing so creates sort of the equivalent
of a tapered impedance transition. Interesting ...
Please Visit Empower RF's Website in Appreciation
of Their Support
Empower RF Systems is a global leader in power
amplifier solutions. Empower RF Systems is an established and technologically superior
supplier of high power solid state RF & microwave amplifiers. Our offerings include
modules, intelligent rack-mount amplifiers, and multi-function RF Power Amplifier solutions
to 6 GHz in broadband and band specific designs. Output power combinations range
from tens of watts to multi-kilowatts. Unprecedented size, weight and power reduction
of our amplifiers is superior to anything in the market at similar frequencies and power
FCC Proposes CB "Type Acceptance" - Manufacturers
Blamed for Malpractices
In all-too-typical style, the Federal Communications
Commission (FCC) decided to look for a scapegoat it could not just blame for but strong-arm
a solution for claimed problems plaguing
Citizen Band (CB) radio as it was rapidly becoming a popular hobby in the 1960s.
In the same manner in which bureaucrats blame gun and steak knife manufacturers for the
abusive actions of a minority of their products' users, the FCC sought to curtail improper
(maybe even illegal) operation of CB radios by imposing type certification and feature
restrictions on equipment manufacturers. To demonstrate its magnanimity , though, the
FCC offered to give companies half a year to deplete their existing inventories. At the
time and through 1977, CBs had 23 channels, after which time 40 channels became the new
Reactel: RF & Microwave Filters of
has become one of the industry leaders in the design and manufacture of
RF and microwave filters, diplexers,
and sub-assemblies. Through a continuous process of research and development, they have
established a full line of filters of all types - lowpass, highpass, bandpass, bandstop,
diplexer, and more. They offer the generally known tubular, LC, cavity, and waveguide
designs, as well as state of the art high performance suspended substrate models. Established
in 1979. Please contact Reactel today to see how they might help your project ...
DARPA Announces Next Phase of Electronics Resurgence
"Expanded program portfolio seeks to increase
access to DoD-specific electronics manufacturing capabilities, enhance hardware security,
and ensure ERI investments translate to DoD applications. First announced in June 2017,
Resurgence Initiative (ERI) - a five-year, upwards of $1.5B investment in the future
of domestic electronic systems - is rolling out the second phase of its research priorities.
Comprised of several ongoing DARPA programs – including the six recently awarded ERI
'Page 3' programs - ERI addresses long-foreseen obstacles to Moore's Law and the challenges
impeding 50 years of rapid progress in electronics advancement. The next phase of ERI
will focus ..."
Please Thank IPP for Their
Innovative Power Products (IPP) has over 30 years
of experience designing & manufacturing RF & microwave passive components. Their
high power, broadband couplers,
combiners, resistors, baluns, terminations and attenuators are fabricated using the
latest materials and design tools available, resulting in unrivaled product performance.
Applications in military, medical, industrial and commercial markets. Take a couple minutes
to visit their website and see how IPP can help you today ...
Blog: Which Bus is Best for Instrument
TotalTemp Technologies has posted a new blog titled,
"Controlling Instruments with GPIB, Ethernet, USB ... or What is Next?
At least 5 busses - GPIB, USB, parallel, Ethernet, and serial - are in use today, each
with unique advantages. Sometimes, especially with older test equipment, you do not have
a choice. " Selecting the right computer bus for your test equipment is a little bit
of a moving target but fortunately is moves fairly slowly and moving in the direction
of better. RS-232 - originating back in the early 60's, RS-232 was developed as a standard
for serial digital communication. Connecting computers to other computers, or remote
instrument communication with a minimum number of wires was the primary use ..."
Before there were vacuum tube and semiconductor
diodes for use as RF signal detectors, there was the
coherer. This article by Henry Davis in the May 1967 Popular Electronics
magazine discusses the invention of the coherer by Dr. Edouard Branley. Dr. Branley's
work was, as is often the case for the ultimate inventors of a new apparatus or process,
based on predecessors who over time pieced together the puzzle of electromagnetic energy
and its effects on objects located some distance from the source. Coherers rely on relatively
strong, broadband energy like that emitted from the early spark gap transmitters in order
to function; both being extremely crude methods compared to modern techniques. The important
thing is that the system worked and provided a springboard for rapid ...
2 Companies Help Navy Develop SWaP Low-Band
"Two U.S. defense companies are helping the U.S.
military in an urgent effort to develop low-band tactical RF jammers for low size, weight,
and power consumption (SWaP) applications on the U.S. Navy EA-18G Growler electronic warfare
(EW) carrier-based aircraft. Officials of the Naval Air Systems Command at Patuxent River
Naval Air Station, Md., are looking to L-3 Technologies Communications Systems-West in
Salt Lake City, and the Northrop Grumman Corp. Mission Systems segment in Bethpage, N.Y.,
to investigate the use of existing technologies to develop a low-band tactical jammer
for the EA-18G aircraft. L-3 and Northrop Grumman ..."
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
Building a Time Machine for Radio
Radio Spectrum Archive is a pretty amazing application of Software
Defined Radio (SDR). You will want to watch the short demo. "The Radio Spectrum Archive
will let you listen to old broadcasts as if they were live. Thomas Witherspoon is building
a time machine, of sorts. With it, you'll be able to pick a date and tune through an
entire broadcast band as if you had a radio that could pick up transmissions from the
past. Sure, well-established shows already make past episodes available, but with Witherspoon's
time machine you'll be able to hear not just that programming but everything else that
was on the air as well: the local news, the commercials ..."
Messages by Meteor
Meteor scatter (aka meteor burst) communications
is today largely the domain of amateur radio operators in their ongoing attempts to set
records for making long distance (DX) contacts with a minimum amount of transmit power.
When this article was written by U. California's Victor Latorre, transcontinental fiber
optic cables did not interconnect the world with high speed, phase stable media that
meets the exacting needs of precise time synchronization. Radio astronomy, quantum physics
experiments, and even stock market trading depends on microsecond or finer timing. Mr. Latorre
mentions here about using
meteor scatter communications' unique phase-stable characteristic to send synchronization
signals between scientific and navigation facilities. Of course meteor scatter has the
severe disadvantages ...
7 New Materials Invented in 2018 that Could
Change Our Lives
It seems a tad early to be publishing year 2018
top stories since we still have two full months available for at least an 8th breakthrough
that could change our lives. "We, humans, are always on the path of inventions and innovations.
In addition to building new technologies and machines, the invention of new materials
greatly influences the future of products and their manufacturing processes. Wondering
what are the best materials invented in 2018? Here they are. The strongest biomaterial
known to man was the Spider silk, which is pound to pound stronger than steel. Many types
of research have made to either replicate this material on a large scale or even surpass
the spider silk in terms of strength ..."
ConductRF Hi-Flex RF VNA Test Cables
Hi-Flex VNA Test Cable Series offers customers superior solutions for applications
up to 70 GHz. Excellent class leading phase & amplitude stability for dynamic
high-frequency testing, demonstrated by Internal flex testing results of better than
±5° & ±0.05 dB respectively over repeated 8 hours flexing cycles. With a
light armor internal stainless steel construction along with a soft FEP external cover,
and a Nomex weaved covering, this combination provides excellent flexibility and ruggedness
and is industry leading in its stability under flexure. Available connector solutions
include 1.85 mm (V connectors), 2.4 mm, 2.92 mm (K connectors), 3.5 mm
and Type−N. Swept right angle versions are available offering the same high performance
of their straight counterparts in both ...
Power Transfer and Phase Basics
Bob Witte has a short primer on the EDN
website covering maximum power transfer using values of complex impedance and the accompanying
phase relationships of voltage and current. "Welcome to my first blog post that explores
fundamental principles of electrical engineering and attempts to tease out some new insights.
For many of you, this will be a refresh of concepts you already know (or used to know)
but I'll also try to add some new insights into the mix. Jacobi's Law Most engineers
are familiar with the
Maximum Power Transfer Theorem (also known as Jacobi's Law). Figure
1 shows a resistive source and resistive load connected with the aim of transferring
power from the source to the load. This principle can be stated as
POPULAR ELEComics with
an Electronics Theme
It's Election Day 2018, and depending on how the
voting goes, some of us (hopefully not me) are going to need some cheering up when it's
all over. If that includes you, then here is a dose of high tech
POPULAR ELEComics levity to help ease your
"My Side Lost and the World Is Going to End" blues. The first of this set of comics from
a 1967 issue of Popular Electronics magazine could serve as an ironic tribute
to the day. On the other hand, if your side wins and you're on cloud nine, then I suggest
you exercise caution when seeing these comics because the added joviality might cause
you to swoon from overstimulation. Of course if you are not an American or do not care
about elections or happen upon this page after the 2018 mid-term elections, please enjoy
these comics in the usual manner ...
TotalTemp Technologies: Thermal
Platforms for −100°C to +200°C
TotalTemp Technologies has more than 40 years
of combined experience providing thermal platforms.
Thermal Platforms are available
to provide temperatures between −100°C and +200°C for cryogenic cooling, recirculating
circulating coolers, temperature chambers and temperature controllers, thermal range
safety controllers, space simulation chambers, hybrid benchtop chambers, custom systems
and platforms. Manual and automated configurations for laboratory and production environments ...
Closer to 15-Minute Wireless EV Charging
"Scientists at Oak Ridge National Laboratory in
Tennessee have developed
wireless charging technology that they say could fill up a typical
electric car today in under an hour. This represents a six-fold improvement over a similar
wireless charging system they announced in 2016. That plugless EV charging technology,
they report, is now being modified for commercial applications including delivery trucks.
And the team isn't done, says Burak Ozpineci, leader of Oak Ridge's Power Electronics
and Electric Machinery group. They are, he says, working toward the larger goal set by
the U.S. Department of Energy (DoE) to build a portfolio of rapid, safe, and easy electric
Axiom Test Equipment Now ISO/IEC 17025:2017 Accredited
Axiom Test Equipment, a premier provider of electronic
test and measurement equipment rentals and sales, is now accredited in accordance with
ISO/IEC 17025:2017 requirements from the ANSI-ASQ National Accreditation Board (ANAB).
This high-level accreditation is awarded to labs that have demonstrated technical competence,
systematic approaches to procedures, and traceability of measurements to national standards.
Shannon Johnson, Axiom's Vice President of Operations states, "Achieving 17025 accreditation
is an important milestone for the growth of our business and expands the capabilities
of our lab. It opens doors to new markets and gives customers high confidence when they
rent or buy ..."
The Moon: We Look Before We Leap - Ranger 6
Congress was breathing hard down the neck of NASA
Ranger 6 was being prepared for its surveillance mission to the lunar surface.
In 1962, Ranger 3, the first to carry a TV camera, went into orbit around the sun
after missing the moon. Ranger 4 (dubbed "Brainless I") impacted the moon but did
not send back any data. And Ranger 5 lost power after launch and missed the moon
by about 450 miles. Time was running out to collect data for use in fulfilling the challenge
issues by President John F. Kennedy on May 25, 1961, to "...commit itself to achieving
the goal, before this decade is out, of landing a man on the Moon and returning him safely
to the Earth." That challenge was successfully met by the Apollo 11 mission partially
on July 21st, 1969 by landing Neil Armstrong and Buzz Aldrin on the moon ...
Many Thanks to INSTOCK Wireless Components
for Their Support!
INSTOCK Wireless Components designs & manufactures
UHF/RF power dividers, bias tees, GPS antenna signal splitters, DC blocking L-Band splitters,
high-power combiners, and current steering splitters with models in 2-way thru 64-way
configurations with Type N, SMA, TNC, BNC, & QMA connectors covering frequencies
from 10 MHz to 6 GHz. Custom configurations also available including mix-and-match
connector options, IP67 outdoor weatherproof, rackmount, and micro-sized units. ...
Electronics Design 2018 Salary& Career
Last week I posted a link to Part 2 of the
2018 Salary & Career Report, and now here is Part 3, which
reports on salaries (up nearly 10% over 2017, BTW). Being self-employed, my pay has effectively
gone down over the past few years since I keep my prices fixed and low for the benefit
of others. My pay depends on you
buying my stuff. "Although many electrical and electronics engineers
that responded to Electronic Design's latest reader survey are unable to shake
the feeling that they could make more money in another profession without the stressful
conditions and punishing workload, two-thirds of respondents actually feel that they
are adequately compensated for what they do ..."
Kaelus's PIM Finder Locates Sources of External PIM Outside
Kaelus, a leading supplier of high-quality, PIM
test and measurement instruments and RF conditioning solutions, has debuted
PIM Finder, software designed to accurately identify and locate external
PIM sources outside antenna infrastructure. Used in combination with the Kaelus iVA Cable &
Antenna analyzer and the iPA portable PIM analyzer, PIM finder is a software option available
through Kaelus Unify, used to pinpoint and detect external PIM sources such as loose
mounting and cable brackets, fasteners, parapet walls and more, while allowing for the
elimination of key causes of PIM interference. "LTE and 5G high data rate modulation
schemes require clean spectrum to operate to their potential," said Tony Langelaan, Product
Transient Specialists: EMC, EMI,
RFI Test Equipment Rentals
Transient Specialists specializes in
EMC test equipment rentals
and carries a complete line of ESD guns, surge immunity test equipment, and EFT generators.
Rentals available for military (Mil-Std 461), automotive (ISO 7637), and commercial (IEC
61000-4) EMC testing. Flexible terms, accredited calibrations and technical support on
EMC testing equipment offered. Equipment consists of top EMC Test System manufacturers,
including Teseq, Thermo Keytek, EM Test and EMC Partner ...
Smartphone Market Continues to Plunge
smartphone shipments have declined for the past four quarters and
the overall market has followed. At the same time Huawei continues to go from strength
to strength. Annual smartphone shipment growth of 41% allowed Huawei to take second place
in the global rankings last quarter and 32% growth this quarter was enough to keep Apple
at bay once more. Samsung's shipments declined by 13% this quarter and if these trends
keep up Huawei could grab the top spot before long - a previously unthinkable event.
'Global smartphone shipments tumbled 8% annually from 393.1M units in Q3 2017 to 360.0m
in Q3 2018 ..."
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