A Bit of TV History
It
is the opinion of historians that in order to understand the present, you need to
know the past. Searching for one's roots in this world is big business. Online family
tree type websites are used by thousands of people to research their family histories,
and some services don't come cheap. You can even pay someone to dig into your past
to assimilate all available information and put it in a bound, printed volume. Here
on RF Cafe, I research and post a lot of our profession's past. While
the individual topics themselves might no bear significantly on the present, having
an insight into the people's mindsets and progression of technology is
...
Needing Only Single 3V
Supply
BeRex-WB-Digital-Variable-Gain-Amplifier-Single-3V-Supply-1-30-2015.htm" >
State-of-the-art BeRex-WB-Digital-Variable-Gain-Amplifier-Single-3V-Supply-1-30-2015.htm" >digital
variable gain amplifiers provide very low power consumption. BeRex today announced
the BVA303 and BVA305, 6-bit DVGA (Digital Variable Gain Amplifiers) offering high linearity,
low noise and require only a single 3V power supply, thereby reducing the power
consumption. Both DVGAs are capable of working at up to 4GHz without external matching
components and are provided in a space saving 4x4mm, 24- pin QFN package. Designed
primarily for 3G/4G wireless infrastructure equipment, satellite radio and other
high BeRex-WB-Digital-Variable-Gain-Amplifier-Single-3V-Supply-1-30-2015.htm" ...
AC alternators
replaced
DC generators back in the 1940s as demand for conditioned electrical
power in vehicles rose beyond that needed for ignition and lighting. Radios are
the most notable additions, and because AM broadcasts were the dominant method of
the day for commercial stations, noiseless electrical supplies were required. Spark-induced
noise from ignition systems was bad enough since its frequency varied with engine
RPM, but the DC generator's commutator sparking noise - much of it right smack in
the audio frequency range - was just too much for the public to endure if widespread
acceptance of radio was to be realized. Remember that in the era, a radio was not
standard equipment in cars and trucks so customers needed
...
This is
my second batch of useful
RF &
microwave articles for 2015 editions of the industry's premier engineering magazines.
The selection, as always, reflects my personal preferences, but I do throw in a
few that just plain look interesting. It's shaping up to be a great year for articles.
-
Software-Designed Instrument
Revolution,
B. Driver &
V. Fernandez
-
Internet of Things Focus,
M. Ouzillou,
R. Yu,
-
Wideband Omnidirectional
Microwave Cloaking,
N. Cohen
-
Extracting Space from
Aerospace & Defense,
D. Robinette
-
Metamaterial Resonators:
Theory and Applications,
U. Rohde,
A. Poddar
-
The Myth Called "Ground,"
B. Archambeault
<more>
After having begun
my electronics career in the USAF as an
airport surveillance radar technician, my interest is always piqued
by articles on the subject. Like so many other types of electronics, radar is so
common today that not many people think it is anything special - just another convenience
that has been around for as long as they can recall - and indeed it likely has been
since radar was first put into practical operation in the early 1940s. In 1945,
the last year of World War II, Radio News magazine ran a multi-month
series on radar system theory of operation and design. When I look at the detailed
block diagram, it brings back
...
One of Melanie's old (and getting
older...☺ ) college
friend posted this list on Facebook. There is evidently no end to the amount of
cleverness out there. Enjoy.
- When chemists die, they
barium.
- I know a guy who's
addicted to
brake fluid. He says he can
stop anytime.
- I'm reading a book about
anti-gravity. I can't put it
down.
- Broken pencils are pointless.
- √☺
* √☺
= ☺
- They told
me I had Type A
blood, but it was a Type O.
<many more>
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. Regardless of the era, the electromagnetic frequency bands
are always deemed to be too crowded so researchers
...
12-18 GHz Power Divider
Werbel-Microwave-12-18-GHz-Power-Divider-1-27-2015.htm" >
Werbel Microwave designs and manufactures custom
Werbel-Microwave-12-18-GHz-Power-Divider-1-27-2015.htm" >power dividers to your
specification with no minimum order. The
2PA1500 shown here covers 12-18 GHz with
1.5:1 VSWR, 17 dB minimum isolation and 0.6 dB maximum insertion loss. Its
footprint is only one square inch. SMA female.
You have just enough
time to get your last-minute
Super Bowl party gear at a good price. Standard
shipping is free, as is 2-day service if you're a Prime member. I justify promoting
the Super Bowl as an RF Cafe Featured Product because of its relevance to the posting
I just did on Roman numbers. Anything you buy on Amazon after than clicking on this
thumbnail helps pay my bills. Thanks.
- As I Imagined It ...
Dr. Lee DeForest
might have had something like National Public Radio (est.
1970) in mind when he penned this article in 1933. In it, the famous vacuum
tube amplifier inventor lamented and criticized the commercialization of broadcasts
because of all the paid product announcements (aka commercials)
that had been steadily increasing over the years. He also was critical of the "hit-or-miss,
higgeldy-piggeldy mélange program basis" of programing; i.e., the same station playing
a mix of jazz, opera, swing, syndicated story-telling, etc. The good doctor did
not elaborate on where funding for such dedicated, uncorrupted broadcasts would
originate if not from paying advertisers, and I do not recall ever reading about
a DeForest Radio Network paid for by his vast fortune. I don't
...
Superheterodyne Datasheet
As
in the past, I am posting these Radio Service Data Sheets as a service
to someone who might be doing research on vintage radios and/or restoring one. Roamio
is not producing automobile radios anymore, but they do now make
TiVo recorders and streaming media players. The
Crosley Roamio Automotive T.R.F. Receiver Models 90, 91 and 92
and
Crosley Roamio Automotive Superheterodyne Models 95 and 96 were
made in the early 1930 at a time when cars and trucks were just starting to experience
such luxury. Crosley did not begin manufacturing its own line of cars until
1939, so none of these radios made it into Crosley autos.
77 GHz Radar Sensor
Sivers-IMA-77-GHz-Radar-Sensor-1-27-2015.htm" >
Sivers IMA is expanding its radar sensor portfolio
by launching a
77 GHz radar sensor. "The need for measuring
distance, depth, speed or position in different products operating in harsh environments
is growing and our radar sensors provide an excellent and cost effective way of
doing that," says Robert Ekström, CEO of Sivers IMA. The new 77 GHz sensor
complements the existing sensors in the 10 and 24 GHz frequency bands. With
its higher frequency, it delivers a signal Sivers-IMA-77-GHz-Radar-Sensor-1-27-2015.htm"
...
A Roman Numeral Review
If you have a hard time interpreting
- or even care about - the Roman numerals used to designate which number in the
Super Bowl series
this Sunday's game represents, you're in good company. My guess is that most people
might be able to interpret a number like III as 3, or even XXXVIII as 38, but something
like XLIX (49 - this year's Super Bowl number) causes
Excedrin headache number XXIV to set in. Excedrin Headache #24 Commercial Even if
you are are familiar with the Roman numeral system, did you realize that there is
no character to represent zero (0) or that negative
Roman numerals do not exist, formally, either? Zero was considered sacrilegious
back in the day because it was considered an affront to a Creator who, it was reasoned,
could never create nothing so there was no need for a number to represent what didn't
exist ...
The extensive unification of
Byzantine fault tolerance and SMPs has investigated flip-flop
gates, and current trends suggest that the study of agents will soon emerge. In
our research, we verify the evaluation of linked lists, which embodies the essential
principles of cryptoanalysis. Here we prove that Markov models and superpages can
synchronize to fulfill this objective. Unified ubiquitous communication have led
to many natural advances, including the partition table and lambda calculus. In
this position paper, we prove the improvement of access points
...
Hogarth
is a comic character invented by the Echophone Radio Company. Their bespectacled
Army grunt was one of the first technology nerd types who always managed to appear
with pretty girls. His caricature evolved quickly over the two or three year run
of the advertisements. Most Echophone Radio ads I have seen either feature Hogarth
and his woman/women or Hogarth and a demanding sergeant. This full-page advertisement
appeared in the August 1945 edition of Radio-Craft magazine. Echophone
radios can still be found on eBay for fairly low prices - often less than the
...
Hmmm..., I
think this article ended up being scanned because an
electronics-themed comic appeared on the same page. Oh well, the
information about building a simple, one-tube television flyback and yoke tester
is still useful to somebody out there, so here it is.
New Product Manager
Pasternack Enterprises, Inc., a leading manufacturer
and supplier of RF, microwave and millimeter wave products, welcomes
Mr. Tim
Galla as the company's Product Manager for Active RF Components. Mr. Galla brings
25+ years of product development, applications engineering and business development
expertise to Pasternack from many of the RF/microwave industry's most recognized
names. Mr. Galla has a successful track record of developing and introducing market-differentiating
products and creating new market
from Sun and Stars
National
defense needs have pushed back the frontiers of science and technology since time
immemorial. Mechanics, chemistry, medicine, mathematics, psychology, astronomy,
electricity, and as of the late nineteenth century, electronics. Astronomy was useful
as a navigational tool and required a very sophisticated knowledge of geometry and
algebra to make it accessible to seafaring men, cartographers, and land surveyors.
Since the early 1900s,
radio astronomy has played a huge role in the advancement of super-sensitive
receiver designs. Most people think of information arriving to them in two or maybe
three forms: sound, visible light, and some (but not many)
even consider radio waves. As over-the-air AM and FM radio broadcasts die out, even
fewer people are aware of radio
...
David Sarnoff
"Television is likely to
do more to revolutionize politics than sound broadcasting did. Political candidates
may have to adopt new techniques to benefit from visual radio: their dress, their
smiles and gestures, all will be important. How they look, as well as what they
say, may determine to an appreciable extent their popularity. The eyes of the public
will be upon them." - David Sarnoff, head of RCA, in his annual report
on the state of television and radio. March 1948
Radio Craft magazine.
Pay Raises Are Bad
Pay
raises are bad for the country. That was according to the Office of War Information's
War Advertising Council's full-page spread in the 1945 edition
of Radio News magazine. According to their logic, you requesting or expecting -
even accepting - a pay raise was damaging to the country's war effort because the
ultimate result was increased prices for end users of products and services. It
was an argument against inflation at a time when inflation was low . At the time,
people had the best interest of the country at heart and, especially with the fate
of the free world on the line, were largely willing participants. Having so many
family members serving in foreign lands in a battle to beat back
...
January 2015
anatech-january-2015-newsletter.htm" >
Anatech Electronics, a manufacturer of anatech-january-2015-newsletter.htm" >RF
and microwave filters, has published its January 2015 newsletter. As always,
it includes both company news and some tidbits about relevant industry happenings.
This month, Sam Benzacar reports on news about LTE Direct, GaN-on-diamond substrates
for high power devices, the World Health Organization findings on RF exposure levels'
effects on kids' health, and microwaveable food packet technology. He also opines
on the topic of "Interference and the New Year." Being a major manufacturer of filters,
Anatech Electronics has a vested anatech-january-2015-newsletter.htm" ...
January 26, 2015
Plenty
of career enhancement and job seeking advice has been published in the ten days
since I last scouted out these kinds of short articles. Of course there is a lot
more where these came from. A caveat emptor warning is prudent when deciding which
bits of career coaching prose to take seriously. I routinely detect political and
sociological biases and attitudes in way too many.
- Things You Should Never Do
When Giving a Presentation
-
New Year, New Skills: Tech
Hiring Trends for 2015
-
How Job Seekers Can Boost
Their Communication Skills
-
The Highest-Paying States for
Tech Pros <more>
Sound effects
in television and movies are in the modern era generated electronically at the push
of a button or the clicking of a mouse. Thousands of sound effects are available
for download to enhance amateur videos. Whether you need the clopping of horse hooves,
birds chirping, a street racer squealing his wheels coming off the starting line,
or a baby crying in the background, it's all at your disposal - and usually at no
cost. Prior to around 1960, with the exception of the incredibly phony sounding
'canned' laugh tracks and audience clapping used on 'live' situational comedies
and variety shows, all those aforementioned sound effects had to be created
real-time in the recording studio. Even if you are too old to
have actually listened to old time radio shows like The Lone Ranger and
The Shadow, surely you have watched an old movie where a gun shot was heard
...
Crossword Puzzle
This is likely the
last engineering-themed crossword puzzle that I will be creating. It
takes about an hour to make and publish each one, and since I suspect the number
of dedicated cruciverbalists out there are few, it is just not worth the effort
anymore. Without any memorable exceptions, I have created a crossword puzzle every
week since sometime in the year 2000 (more than 700 total).
Each one was made with personally selected words to avoid non-relevant terms and
clues. The puzzles will resume if enough requests come in to do so, otherwise, today
marks the end of an era.
in That Coil?
This
is a nice short article covering the
calculation of inductances for coils wound on cores and wire sizes.
The author recognized that standard formulas, although concise and accurate, are
sometimes difficult to work with when calculations for a large number of values
is needed for a particular circuit design. To address the situation, he presents
a handy nomograph, chart, and a table of typical values. A smartphone app, a spreadsheet,
or a desktop computer program would be used today to calculate inductance values,
number of turns, winding spacing, etc., but back when mechanical slide rules were
the order of the
...
In his 1948 editorial titled
"Radio in the Next War," Hugo Gernsback predicted no fewer than
four major technological milestones. The first two were actually foreseen in his
pre-World War II articles where he wrote of what would become known as 'radar'
and the 'Handie-Talkie.' With war against the Commies in North Korea brewing, he
wrote of both cruise missiles, NORAD, and the concept of MAD
(Mutually Assured Destruction) as it pertained to
the U.S. now being the first to detonate a nuclear weapon henceforth. For more than
70 years the prediction has held. You need to be a pretty good judge of both technical
capabilities and their developmental timelines
...
It's Friday and the
weekend is almost here - time for little levity. These
comics from Radio-Craft magazine have an electronics
theme, so you can claim looking at them is work-related since you might use one
for your next conference or project status presentation. Some of the concepts are
utterly foreign to contemporary readers, like user-serviceable electronics apperati[sic]
and radio sets that receive over-the-air signals. There is a list of many more similar
comics at the bottom of the page in case you haven't seen them yet. Enjoy
...
I will be on
the road for most of today and tomorrow, so responses to e-mail will be delayed
a bit. Thanks for your patience.
If this article
had appeared in an April edition of Radio-Craft, I might have suspected
it was a Fool's hoax, but it was the March issue and, it turns out, it was serious.
Obviously the concept of a filamentless tube did not work out well since the overwhelming
majority of vacuum tubes sold up until the time semiconductors took over the electronic
device market had separate filaments (heaters). It
was a great idea, though, and the world is thankful for the pioneers who take the
figurative 'arrows' for the rest of us. We benefit from their hard work and ingenuity,
while they suffer the agony of defeat, with an occasional taste of the thrill of
victory. It is too bad the concept did not work because, as pointed out in
...
Through Your House Walls
L3 Comms'
Range-R handheld
radar
unit is capable of 'seeing' through building walls to detect a building's contents.
It was evidently developed for military operations when conducting house-to-house
searches for jihadist terrorists in places like Afghanistan and Iraq. Like much
military technology, though, it is being adopted for use by civilian police, federal
law enforcement agencies, firefighting, and search & rescue teams. Range-R's
ability to "detect and measure the distance to moving and near-stationary personnel
through walls constructed of common building materials" makes it an ideal tool for
looking for survivors inside collapsed buildings, for finding incapacitated and/or
trapped people within burning homes, and for allowing law enforcement personnel
to determine the presence and
...
Noise Amplifier Family
Guerrilla-RF-Ultra-Low-Noise-Amplifier-1-20-2015.htm" >
Guerrilla RF Inc., a leading provider of high
performance MMICs, today introduces an Guerrilla-RF-Ultra-Low-Noise-Amplifier-1-20-2015.htm" >ultra-low
noise amplifier family with industry-leading noise figure and the highest level
of performance. These new high linearity solutions support a number of wireless
infrastructure devices including high performance small cell LNAs, macro base station
LNAs, distributed antenna systems (DAS) and general
purpose LNA applications requiring the absolute lowest possible NF. "We are excited
to help our wireless infrastructure customers obtain maximum receiver sensitivity
and improve receiver dynamic range with minimal external components, which ultimately
Guerrilla-RF-Ultra-Low-Noise-Amplifier-1-20-2015.htm" ...
Operation Worm Warming
When
becoming a licensed Ham a few years back, I learned that when broadcasting over
amateur bands, the FCC requires you to transmit your station identification at the
beginning of each session and then at least once every ten minutes. I hate to nit
pick a
Carl & Jerry story, but in this episode John Frye's intrepid
electronics hobbyist duo rigs up their basement 'shack' to automatically transmit
the letter 'A' in Morse code as a beacon signal to test reception in a cave. A timer
would start the broadcast and it would run continuously for half an hour. Maybe
things were different in 1961. The experiment intended to test a signal's ability
to propagate through the Earth rather than through the air. It is an interesting
twist on the skin effect of high frequency signals along a conductor
...
to Electrical
Wiring
David Herres has sharpened
his pencil and written a couple new books for the DIYer tackling electrical wiring
issues at home.
The Homeowner's DIY Guide to Electrical Wiring
goes beyond the typical book of this sort and devotes considerable space to modern
electrical devices like wide screen TVs, computers, wireless devices, alternative
energy, home automation, satellite receivers, etc. He also discusses electrical
services, specialty devices like ground fault and arc fault interrupters
(GFIs and AFIs), recent National Electrical Code changes,
and much more. Stay tuned for a review and accompanying quiz on David's
The Electrician's Trade Demystified.
Antenna
Antennas
have been deployed in difficult environments using many ingenious methods over the
years both by professionals and amateurs. The process typically involves first propelling
a lightweight string or wire across and/or up to a supporting structure
(a tower, tree, building, whatever) and then using
that lead line to draw the antenna and its accompanying coaxial or twin lead cable
into its final position. Sometimes simply tying a line to a rock and tossing it
over a tree branch does the trick, but usually deployment requires a more powerful
launch such as a a bow and arrow or even a model rocket. Many years ago a modeling
magazine reported on a large radio controlled airplane that towed a lead line across
a wide gulch
...
to Engineering Magazines
Many of your favorite
magazines offer free subscriptions
to qualified applicants. Qualified usually means that you are currently employed
in a field related to the primary theme of the magazine, and often you also need
to be a decision maker for buying products represented within the pages. The list
hasn't changed much - if at all - since last month. Technical
magazines, like RF Cafe, get paid by advertisers and therefore need the public
to support those companies by purchasing their products and/or services. If you
think you meet the standards
...
Week of January 20, 2015
"Earth is not a magic drain into
which all of unwanted RF can be poured via a wire." --
H. Ward Silver, N0AX, ARRL author of "Hands-On Radio" column in QST
(January 2015). Mr. Silver is also the lead editor
of the ARRL Handbook.
Modulation - Part II
This
is the second and final installment of an article on the topic
frequency modulation that began in the July 1941 edition of
Radio-Craft. Author Raymond Guy, a radio facilities engineer at the National
Broadcasting Company (NBC), covers all the fundamentals
of FM not just from a functional circuits perspective but also pointing out a broadcaster's
concern for channel spacing and broadcasting ranges. Transmitter pre-emphasis, receiver
de-emphasis, noise thresholds, and adjacent channel and co-channel broadcasting
strategies are discussed here.
The Latest Engineering Articles
I know you're busy, so I took
the liberty of linking to a few recent articles from Microwave Journal, High Frequency
Electronics, and Microwaves & RF that look interesting. That's not to say the
others are not, but this is the kind of stuff that piques my curiosity. The overly
scholarly articles make my head hurt, so I gravitate toward practical advice and
whiz-bang new technology.
-
Wideband Omnidirectional
Microwave Cloaking, N. Cohen
-
Sorting Through Balun
Confusion, D. Jorgesen
-
Changing the Operating
Frequency of an RF Power
Amplifier Circuit, (p.22)
D. Vigneri
-
Real Time Radar Target
Generation, S. Heuel,
D. McCarthy
- Antenna Tackles Wi-Fi and
WiMAX, M. Shafiei,
M. Moghavvemi, W. Mahadi
and Why of Frequency
Modulation
Here
is the first of a two-part article on frequency modulation. FM was a very welcome
option for entertainment radio listeners who had grown weary of static mixed in
with their music and syndicated adventure, drama, and comic programs like The
Green Hornet, Lights Out, and The Life of Riley, respectively.
Amplitude modulation is susceptible to all sorts of interference from car ignition
systems, arcing in electric motors, light switches being turned on and off, lightning,
and a host of other sources. A commercial radio with good noise and adjacent channel
rejection was relatively expensive. Permanent magnet speakers did not become a standard
feature for first few
...
Modular Smartphone
A
lifetime ago (in technology advancement time units)
I reported on a crowdfunded project to develop a
modular smartphone
called Phonebloks. The idea was
to sell a plug-and-play building block platform where the user decides exactly what
functionality he/she needs and what level of functionality, and then simply plugs
the modules into a motherboard type base. It would also permit owners to upgrade
and/or swap out only functions deemed necessary. So, if you believe that a 12 Mpixel
camera sensor chip being used with a cheap plastic lens is an unwarranted expense,
then buy the 5 Mpixel camera module with the same lens and same picture quality
for half the price, and at the ...
Communications Forum
EDI-CON-5G-Advanced-Communications-Forum-Conference-Sessions-1-7-2015.htm" >
Horizon House Publications and Microwave
Journal China are pleased to announce that
EDI CON 2015, taking place April 14-16, has added a 5G Advanced
Communications Forum to the conference schedule. The 5G Forum will be a full day
of sessions taking place on April 15 at the China National Convention Center . The
5G Forum will kick off with China Mobile presenting their perspective on 5G technologies
followed by a panel session including experts from organizations such as China Mobile,
Shanghai Tech, Keysight Technologies, Rohde & Schwarz and National Instruments.
A EDI-CON-5G-Advanced-Communications-Forum-Conference-Sessions-1-7-2015.htm" ...
Puzzle for January
18, 2015
This week's
Wireless
Engineering crossword puzzle contains the usual collection of science, math,
and engineering terms, and also includes a couple topics that have been in the technical
news headlines lately. Enjoy.
Tubes Back to Life
If this article
had appeared in the New York Times in the year 2014, its author, Glenn Ellsworth, would have been labeled a 'Depression Denier!'
Don't be confused by the word 'denier,' which most often prior to about 1999 was
used to refer to a type of silver coin or a measure of fineness of silk cloth. Today,
it is seen most often as describing one who would deny something. 'Denyer' is the
alternate spelling used by some authors to avoid confusion, and since the level
of spelling knowledge is so low, most people never notice. But, I digress. The reason
I bring up the point is because this article was published in 1933, little more
than three years after the Stock Market Crash of October 29, 1929. Mr. Ellsworth
says in part, "Many service departments are fairly busy, even with the so-called
depression at its
...
Resources for January 16, 2015
Infographics are
a big deal in communications these days. A lot of the artwork is really impressive,
but let's face it, infographics are basically kindergarten picture books for adults.
Even so, I like them - pass the milk and cookies. The first item on this week's
list is in fact an infographic with recommendations on
avoiding resume
mistakes. Don't expect a 'wow' factor in the pictures, though; it looks as though
everything came from the MS Office clipart collection.
-
Resume Mistakes Job Seekers
Must Avoid [Infographic]
-
How to Ask for a Raise – and
Actually Get It
-
The Single Best Way to
Answer Every Job Interview
Question
-
My First 90 Days: Interview Is
Just Beginning, <more>
Today we have
missing persons notices printed on milk cartons and computer-aged
pictures of missing kids on bulletin boards at Walmart, and of course the Internet
with all its various forms of publicity. In 1935, evidently, an electronics magazine
was a proper venue for placing a missing person ad. At the time there was no convenient
and accessible way for family members to reach out to a nationwide audience other
than to place ads in magazines and/or newspapers in remote locations. I thought
it odd to see such a placement in this edition of Short Wave Craft, but
considering the aforementioned, doing so is entirely reasonable for a worried family.
It's heartbreaking, really
...
