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of archive
 Arthur Steele is probably enjoying retirement
from
Littelfuse by now. In 1965 he had an article published offering
guidelines on how to select the proper type fuse for protecting the circuit at hand.
The correct choice is seldom a simple matter of adding a margin of some amount onto
the known maximum current draw, especially if you are designing for a commercial
or defense electronics project. Applied voltage, expected current surges, operational
temperature and mechanical stress (vibration & shock, etc.), applicable design
regulations (UL, Mil-Spec, etc.), serviceability, and available space are among
the factors that need consideration. Do you need a fast-blow, medium-blow, or slow-blow
fuse for that circuit? You'll have...
 Joe Cahak has come through again with more
examples of engineering cardboard calculators. These things were the "App" of choice before
smartphones were the rule rather than the exception. Added this time are an electrical
units converter and connector selector by MegaPhase, and two types of memory configuration
wheels for the HP 9000 series 200 and 300 computers. Your donations would be appreciated
- high-res photos are acceptable in lieu of physical devices...
 For many years I posted a weekly "Cool Pic"
item derived from articles I read in magazines and websites. I'm not sure why I
stopped doing so - probably due to lack of time - but seeing this über-cool-looking
16-element antenna array
that operates at 83 GHz prompted this post. At initial inspection it appears
to be a 16-port switch unit because unless you are familiar with how small an 83 GHz
antenna can be, those devices hanging off each port look like push-on coaxial connectors,
but they're not. This work is being done by engineers at the NIST in a project researching
how to best increase available wireless channel frequencies and bandwidth...
 A
while back, I posted information on a vintage General Electric (GE) analog
AM/FM clock radio that I bought on eBay. It is a model I had as
a teenager while living at home. As with most, if not all, AC clocks of the day,
it used a synchronous
motor to drive the clockworks - in my case a set of rotating numerals for displaying
the time in increments of minutes (no seconds display).
Synchronous motors, as the name implies, rotates at a rate proportional to the frequency
of the alternating current that drives it. In the United States the AC line frequency
is 60 Hz. In the United Kingdom, the frequency is 50 Hz. Consequently,
a clock designed to work at 60 Hz will run...
 Narrow-band frequency modulation (NFM) was
a relatively new technology in 1947, having been advanced significantly during World
War II. Amateur radio operators were just getting their gear back on the air
after having been prohibited from transmitting for the duration of the war. Few
were probably thinking about adopting and exploiting new modulation techniques,
but for those who were and recognized FM as the path to the future of radio, QST
published this fairly comprehensive treatment of both frequency modulation (FM)
and phase modulation (PM). Mathematically, FM is the time...
 I have to admit to not recalling ever having
heard of Dagmar; have you? Crack electronics technician "Red" mentioned her in this
episode of "Mac's Radio Service Shop" appearing in the March 1952 edition
of Radio & TV News. I thought Prince and Cher were the first man
(ostensibly) and woman, respectively, to use a single-name
public moniker, but evidently Dagmar beat them to the punch ...but I digress. John
T. Frye, author of the popular
Carl & Jerry series that appeared later in Popular Electronics
magazine, wrote this series before that time. On this cold and wintry day, Red and
Mac are discussing troubleshooting methods and how looking for and interpreting
certain symptoms...
 For as long as I have been in the RF and microwave
career field*, the
Electronic Warfare and Radar Systems Engineering Handbook, published
by the Naval Air Warfare Center Weapons Division, has been the go-to publication
for high level information on the title's subjects. Unbeknownst to many people who
have forgotten about it or gave up trying to find a copy of it, the publication
was last updated in 2013. According to the Foreword: "This handbook is designed
to aid electronic warfare and radar systems engineers in making general estimations
regarding capabilities of systems. This fourth edition updates technical...
 NI (formerly AWR Corporation) announces that
undergraduate students at the University of Peradeniya (PDN) in Sri Lanka designed
a unique multistage coupler using NI AWR Design Environment™ circuit design software, specifically
Microwave Office. The students designed and simulated a unique wideband coupler
that improves directivity by increasing the number of stages of the coupled line
coupler, resulting in improved bandwidth performance, directivity and phase compensation...
 This article by
Joshua Fruchter, writing for
IMS ExpertServices, reviews a recent patent infringement lawsuit
and the contortions used by legal 'experts' to argue whether the designers of a
laser-equipped board game knowingly used features of a pre-existing
game as a springboard for their product. As pointed out by Mr. Fruchter, the rationale
used by the judge in his ruling illustrates the often fine line separating malicious
intent from ignorance. Even in the appeal, the final ruling is a case study (pun
intended) of subjectively arrived-at conclusions versus objectively arrived-at conclusions.
Definitions of "a skilled artisan," "prior art," and...
 "Only the ideas that pass through a rigorous
self-filtration make it out and are criticized by the rest of the scientific community.
It sometimes happens that ideas that are accepted by everybody turn out to be wrong,
or at least partially wrong, or at least superseded by ideas of greater generality.
And, while there are of course some personal losses—emotional bonds to the idea
that you yourself played a role in inventing—nevertheless the collective ethic is
that every time such an idea is overthrown and replaced by something better the
enterprise of science has benefited." -
Carl
Sagan, "The Burden of Skepticism", Skeptical Inquirer, v12.1, Fall
1987
 Pasternack, a leading manufacturer and supplier
of RF, microwave and millimeter wave products, has introduced a new portfolio of
solid state, high power amplifiers. These coaxial packaged RF
amplifiers cover UHF, VHF, L, S and C frequency bands and are widely employed in
applications such as electronic warfare, instrumentation, military communications,
radar, SATCOM, telecom, data links, medical devices and many others. Pasternack's
latest release of high performance RF amplifiers includes...
 The 1940s and 1950s was an era of much advancement
in our knowledge of Earth's upper atmosphere and its affects on radio communications
- both good and bad. Industry, government, academic, and amateur groups all played
major roles in conducting experiments and publishing findings for the interested
community to share and build upon. A year ago I posted an article, along with a
bit of editorialization, from the July 1958 edition of Radio-Electronics
titled "Communications Via Meteor Burst."
RCA Institutes Advertisement
 In the original radio broadcast of Jean
Shepherd's "A Christmas Story," which was set in the Great Depression era, he spoke
of magazine advertisements promising rewarding careers in electronics for men of
adventure. Over the last few years I have posted many such advertisements from vintage
electronics magazines, but they were also commonly seen in women's magazines,
Life, The Saturday Evening Post, and many others. This ad pitching
RCA's home study courses for electronics technology ran in a 1961
edition of Electronics World. Chairman of the Board, David Sarnoff, sends the message
to readers. Sarnoff was...
 Kick back at the end of work today and enjoy
this triad of
electronics-themed comics from 1963 and 1965 issues vintage
Radio & Television News and Electronics World magazines. Other
than an occasional contest to create a caption for a comic drawing, when is the
last time you saw a comic in a technical magazine? Where has the humor gone? Is
everyone so afraid of offending someone that comics have been banned by lawsuit-fearful
editors? You have my invitation to create a good-humored cartoon about me or RF
Cafe anytime you wish, and I promise not to sue you. I'll even post it here on the
website if you like...
 Seamless
integration of wireless communications with wired communications
has not always been a yawn in technical strategy discussions. It has really only
been since the early 1990s with the introduction of ubiquitous cellphone systems
that someone on a wireless device could connect directly with a wired contact and
not need an intermediary operator to facilitate. Some military comms, the Inmarsat
system and a few other proprietary systems were available, but not to the public
at large. This article reports on some of the Army's early attempts at implementing
wireless-to-wired communications, specifically as implemented during the Normandy
Invasion on D-Day (June
6, 1944). Unlike present day systems that rely heavily on data compression and
massive multiplexing, those systems allocated the standard audio (voice)
bandwidth...
 John W., of Plympton, MA, is the winner of
the RF
Cafe May 2015 Book Drawing. He wisely selected
Microwave Mixer Technology, and Applications, graciously provided
by Artech House.
Each month I randomly pick one or two names from the list of people who have ordered
my very inexpensive
software products. Books, usually with a retail value of >$100,
are graciously provided by major publishers like
Artech House and
Cambridge University
Press. I pay packing & shipping from my own increasingly depleted pockets.
John makes the 120th winner since the drawing began in 2009.
 Even with the ready availability of
programmable calculators and smartphone apps, there are still times when having
a handy-dandy
nomograph printed out and hanging on the wall for quick reference can be a
great asset. This nomograph which appeared in a 1965 issue of Electronics
World magazine provided ready conversion between two different (input and
output) voltage and power values to equivalent decibel values. It seems strange
that the watts and voltage scale is on the left and the milliwatts and
millivolts scale is on the right. That might be more intuitive for a nomograph
of attenuation, but not - at least to me - for positive gain as through an
amplifier...
 NI (formerly AWR Corporation) announces sponsorship of the
Besser Associates' MMIC Design Overview Webinar, part of the Microwave
Journal RF/Microwave Training Webinar Series. Presented by Ali Darwish, Ph. D., this
free one-hour webinar gives an overview of some of the practical strategies required
to achieve success in the design of monolithic microwave integrated circuits (MMICs).
Topics covered include: Advantages and limitations of MMIC designs...
 Former
USAF radar technician Elbert Cook, who built this amazing model of the
AN/MPN-13
mobile radar unit that he worked on in the service, recently sent me
more photos of
the fielded system. Interestingly, I was recently contacted by a guy in the UK who
builds software models of airfields for flight simulators and needed accurate scale
data. I put him in contact with Mr. Cook, who is using his many former contacts
to help assimilate the needed information. I'll post pictures of the Sim models
when available - should be cool!
 Here is a really nice write-up on electrical
noise, both how it originates and how it affects receiver systems. Although vacuum
tubes were still the predominant active amplification components in 1965 (the date
of this article), semiconductors were already solidly ensconced in the signal detector
role. I have to confess to learning a new term that I probably should be familiar
with:
Equivalent-Noise-Sideband-Input, or ENSI. It appears also in
Reference Data for Engineers: Radio, Electronics, Computer, and Communications.
Interestingly, this is the first time in a long time I have seen noise referred
to as "grass;" the drawings make it clear why the moniker was created. We were taught
to use "grass" in USAF...
 Saelig Company has introduced the
STD-503,
a 2.4 GHz radio transceiver module, designed to facilitate the simple embedding
of wireless capabilities in industrial remote control equipment. Suitable for worldwide
implementation, this compact radio transceiver module was specifically developed
for industrial applications that must have stable and reliable communication for
up to 300 yards with battery operation...
 Electronics Manufacturing with Lead-Free,
Halogen-Free, and Conductive-Adhesive Materials Hardcover, by John Lau,
C.P. Wong, Ning-Cheng Lee, and Ricky Lee. This comprehensive guide provides cutting
edge information on lead-free, halogen-free, and conductive-adhesive technologies
and their application to low-cost, high-density, reliable, and green products. Essential
for electronics manufacturing and packaging professionals who wish to master lead-free,
halogen-free, and conductive-adhesive problem solving methods, and those demanding
cost-effective designs and high-yield...
 Mr. Thomas Green, of TJ Green Associates
sent me information on his company's latest white paper titled "New Release of Mil-Std-883 Visual Inspection Criteria." Mil-Std-883
is a collection of test methods for microcircuits. Visual inspection criteria for
hybrids and RF MMIC modules and an overhaul of the inspection criteria for passive
components TM 2032 are among the affected topics.
TJ Green Associates LLC provides
teaching and consulting services to companies around the world with expertise in
wirebonding , die attach, visual inspection, hermetic lid seal and hermeticity testing,
and more. If you are in the business, you will want to read this...
... so says Google, anyway, and after all, that's the only thing that matters
these days. People not in the business of publishing a website might not be aware
that as of April 21, 2015, any webpage that does satisfy Google's criteria for displaying
properly in a mobile device viewport is down-ranked in search results that originate
from a mobile device. Supposedly PageRank ratings are not impacted if a user searched
from a desktop computer - only if from a phone. Notice of the intention was served
in the middle of last year and many webmasters, including myownself[sic], scrambled
to learn what the requirements were in order to receive Google's coveted "Mobile-Friendly"
blessing. Basically, the page content must not overflow the device screen width,
text sizes must be a minimum size for...
Barry Manz's
The 2016 Defense Budget in Perspective leads this selection of
articles from the month of May. It provides Barry's unique insight into the industry
based on many years of access to insiders. If you didn't make it to this year's
IMS2015 show in Phoenix, Lou Frenzel has a wrap-up along with an Engineering TV
video. Darn, RF Cafe missed being selected as Best Industry Website this year. Oh
well ...
-
The 2016 Defense Budget in Perspective
-
Correlation: An Overlooked Oscilloscope Measurement
- Wrapping up
IMS 2015
-
Using Power Sensors in Test Sets <more>
 RFMW announces design and sales support for Peregrine
Semiconductor's
PE43711, a 7-bit digital step attenuator capable of maintaining
0.25 dB monotonicity through 4 GHz. Operating to 6 GHz, the PE43711
offers 0.5 dB monotonicity through 5 GHz and 1 dB monotonicity through
6 GHz. Featuring "glitch-less" attenuation state transitions, the PE43711 is
ideal for many broadband wireless applications including 3G/4G infrastructure, land
mobile radio (LMR) and point-to-point communication systems. The attenuator incorporates
both parallel and serial...
 "Heck, many kids today don't even know what
radio is (and don't realize that their cellphones are actually radios)" –
Dan Romanchik, author of
Is Amateur Radio Still a Gateway to Electrical Engineering?
 Before the current generation began destroying
its hearing with smartphone earbuds, their parents and grandparents (that includes
me) destroyed our hearing* with ridiculously powerful loudspeakers, often in boom
boxes perched on shoulders right next to the ears (not me). The "concert hall" -
or concert auditorium - experience has been long sought-after since recorded music
has been available, which has only been about a century. As evidenced by the sudden
increase in articles and advertisements in my growing collection of
vintage electronics magazines, the early and mid 1950s saw a sudden
swell of articles promoting the equally swelling supply of high fidelity (hifi)
recording and playback...
 Arthur Collins
founded the
Collins Radio Company in 1933 to enter the fledgling domestic
AM broadcast market. His equipment instantly became renowned for high quality and
reliability. Collins gained early notoriety as the result of being selected by Admiral
Richard Byrd for his South Pole expedition. The U.S. military took notice and the
company quickly earned a reputation as a preferred supplier of aviation communications
equipment both for commercial and military aviation. As seen in this 1946 advertisement
in Radio News, Trans World Airlines proudly employed Collins radio equipment
in its fleet of Lockheed Constellation (aka "Connie")...
 Narda Safety Test Solutions has launched a new
FFT analyzer for low frequency electromagnetic fields. This device, called
EHP-50F, measures and analyzes electric and magnetic field strengths
in the frequency range 1 Hz to 400 kHz and evaluates the results in accordance with
current human safety standards. EHP-50F from Narda Safety Test Solutions The EHP-50F
from Narda Safety Test Solutions is a new FFT analyzer for assessing low frequency
electric and magnetic fields considering aspects of human safety. It covers the
entire range from 1 Hz to 400 kHz...
 As with most things of consumer, commercial,
and industrial nature, the battery - more correctly "cell" - science has come a
long way in a relatively short time. Alessandro Volta invented the eponymous
voltaic pile in 1799; it consisted of zinc and copper electrodes
immersed in a sulfuric acid electrolyte, thereby being a wet cell. The first dry
cell was the zinc-carbon type invented by Guiseppe Zamboni (not the guy who invented
the ice rink resurfacer) in 1812. Rechargeable dry cells of the NiCad variety hit
the scene in 1899. Then, it wasn't until 1991 - a century later - that Sony commercialized
the Li-Ion cell (and varieties thereof) that now dominates...
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