you have never paid much attention to the state of the art in telescopes, then you
might believe they consist of either the $99 Tasco jobs in Walmart's toy department
or the 200" Hale atop Mount Palomar. You might also think that objects which emit
or reflect light in the visible spectrum are the only things studied. You might
not know that
radio telescopes have been built to detect frequencies ranging
from HF all the way up into cosmic rays. Newer telescopes search for gravity waves
and even neutrino and 'dark matter' pseudo particles. You might not know that there
is a broad selection of optical telescopes for amateur and research grade telescopes
and that the line between amateur and research grade telescopes...
Copper Mountain Technologies releases the new
Planar 808/1 vector
network analyzer, adding to its full size VNA line. CMT makes high performance
PC-driven VNAs at an affordable price point without sacrificing metrological quality.
Planar 808/1 is a four port VNA which operates with an external PC, opening a new
range of possibilities for users who need highly accurate multiport instrumentation
for lab, production, or field use. At just 19 pounds, Planar 808/1 is a more mobile
and transportable solution than a traditional bench top unit. This lab quality VNA
offers an extensive feature set, multiple data saving options, and is fully programmable
for incorporation in automated applications.
Asian Circuits, with its HQ in Toronto, Canada,
and production facilities in China, has emerged as a well known turn-key PCB assembly
service provider. Asian Circuits is known for providing electronic manufacturing
services, including PCB fabrication, components sourcing, and complete electronic
assembly. Our online
PCB assembly quote
generator can help you estimate the assembly cost of your PCB project. We cater
to customers primarily located in the U.S. and Canada.
Linx Technologies announces its launch of the
FM GPS receiver modules. At just 15x13 mm in size, the MediaTek MT3339-based
FM Series gives the module fast lock times and high position accuracy even at low
signal levels. Very low power consumption helps maximize runtimes in battery powered
applications, such as positioning and navigation, location tracking, marine, and
asset management. Simultaneously acquires on 66 channels and track on up to 22 channels.
The GPS receiver is completely self-contained and only requires an antenna.
The RF & microwave trade magazines have updated their online articles for
October. Here are a few that might interest you.
Analyzing the Role of Local
Oscillator Phase Noise in
Reciprocal Mixing, ACS
100W High Power Silicon PIN
Diode SPDT Switches,
Next Generation Wireless:
Riding On the Back of
Measure Vector and Area
with an Oscilloscope X-Y
Display, Arthur Pini
How to Think in dB,
Uncertainties in Spectrum
Analysis, Bob Nelson
Evaluate EDA Software for
a Wireless World,
Dr. Stephen Maas
Beyond CMOS Vs. GaAs:
Pick the Right Technology,
Long before digital communications
was widely adopted, there was a great need for
stable frequency-determining devices / systems. That is to say,
low bit error rates (BER) for digital communications are not the sole motivation
for oscillators with low short-term and long-term stability and low levels of jitter.
One obvious need for precise frequency control is radar, in order for accurate ranging
(the second 'R' in radar) and in the case of Doppler systems, for accurate radial
velocity reporting and clutter cancellation. Those capabilities existed long before
digital systems came online. Aside from radar, precise frequency was needed in order
to reduce guard band width between assigned channel assignments, thereby enabling
more broadcast stations (commercial and military) to coexist in an allotted frequency...
Every Founder Needs to Master" is the theme of the November 2013 Inc magazine
issue. Topics such as "How to Do More of What You're Good at and Less of What You're
Bad At," "How to Take a Fresh Approach to a Staid Old Business," and "How to Really
Connect with Customers," are typical. I scanned over a few to see what the entrepreneurial
business owners had to say about their experiences that they considered most to
be useful. Then, I arrived at the last one, Tip No.29:
How to Be Funny at the Office.
This I had to read. Something just didn't seem right, though, as I progressed through
the story. Take this passage from a Q&A session...
Planar Monolithics Industries (PMI) introduces
PE210R258R515SFFLM Rev. B, a 0.25 to 8.5 GHz, low noise amplifier with
a small signal gain window of +9.0 dB to +13 dB. The noise figure
for this unit is ≤4.5 dB max (valid from 0.5 to 8.5 GHz) and offers
an OP1dB of +16 dB min. The operating voltage is +12VDC and the current
draw is 300mA max. The unit is supplied with removable SMA(F) connectors in
our standard PE2 housing.
Whoa! Take a look at the
RF feedthrough and lightning arresting choke on the feed line on the original
Voice of America transmitter in Munich, Germany. Now that is serious
stuff. This story from an early Popular Electronics reports on the extreme
lengths to which the Soviet bloc went in order to prevent its countrymen from hearing
radio signals broadcast by the Voice of America and other non-state-approved beacons.
Quarter megawatt transmitters sent messages of freedom that could be picked up by
even the most remote crystal sets that didn't have the advantage of amplification.
Ground-wave, sky-wave, and short-wave jamming techniques were employed to ensure
the only signal that could be received was a buzz-saw type noise. Not so long ago,
and certainly in 1959, America was viewed as a beacon of freedom, both figuratively
via word-of-mouth and underground newspapers, and literally via high powered...
RF Cafe contributor Bob Davis
has added another vintage radio to his collection - a
Bendix Model 75P6U AM/FM tabletop radio. More extensive restoration
is planned, but for now just replacing all the electrolytic and wax-paper type capacitors
put the set into working order.
the Chip: Labor Rights and Environmental Justice in the Global Electronics Industry,
by T. Smith, D. Sonnenfeld, and D. Pellow. I've never been one to shy away from
a good argument when it comes to bucking against the ill winds of political correctness.
In general, PCness causes the vast majority to suffer for the benefit of a relative
few who often assert their 'rights' (real or imagined) to special privilege out
of spite and/or self-righteousness. The subject of exploitation of the world's poor
and desperate to the advantage of the rest of us bothers my conscience in a conflicted
manner. On the one hand I realize that the exploited often consider their new conditions
to be better than what they previously endured, but on the other hand there is a
moral obligation to not rationalize away our complicity in the matter. The most
egregious offenders are those who make a lot of noise about profiting from the misfortunes
of said poor while obliviously...
For this week's Featured Book, I wanted to
find something on wire-wrapping. Although I was not successful at finding a book
currently in publication that is dedicated to
I did find a great page on Wikipedia full of information and great high-res pictures.
There are plenty more resources if you do a Google search. Wire wrapping (w/w) used
the be a very popular method for prototyping circuits when DIP and SIP packages
dominated the electronics landscape. If done properly where wraps were placed on
posts in order to make changes easier and where care was taken to avoid crosstalk
from long parallel signals runs, w/w was useful at frequencies into the tens of
megahertz, even with digital circuits. I personally have wire-wrapped more than
a hundred boards both as engineering prototypes and as deliverable assemblies for
military equipment. A well-done w/w board...
Which came first,
the chicken or the egg? The same can probably be asked of
Google and the government's
(NSA, CIA, FBI, DHS, and various other 3-letter agencies) need for a massive data
collection capability that at first glance has the appearance of a benign private
company. Even though Larry Page and Sergey Brin undoubtedly developed and built
Google without any help from the Fed, their current intertwinings with every facet
of government from low level agency personnel all the way up to the prez himself
is unquestionable. You don't get that kind of access and wield such influence without
giving up something in return - usually your honor and personal motto (in this case
abandoning "Don't Be Evil"). We have all witnessed hypocrisy on the part of Google's
executives in the form of a pimped-out Boeing 767 aircraft for globe trotting under
the guise of eco-warrioring, along with special landing privileges at military installations.
Add to that...
everything RF is a search engine for
RF & microwave components. everything RF
lists complete catalogs from various RF & microwave component manufacturers
and enables engineers to search through them by specification. There are over 124,463
components listed from more than 281 manufacturers. Download datasheets, request
quotes or contact the suppliers for more information via everything RF. Its
Fast & Easy!
- Response (referring to AM/FM) given by Ham radio operator when ask by policeman
in Virginia what type of radio he had installed in his car (hat tip to RF Cafe visitor
KA). Virginia DOT requires that "A vehicle displaying Call Letter License Plates
is subject to inspection by DMV or any police officer to determine if the operator
and the vehicle comply with the requirements." You must "Have operational transmitting
and receiving equipment permanently installed in your vehicle." The specific wording
requires Tx AND Rx equipment (AM/FM radio is Rx only and therefore might not qualify),
but that could just be bureaucratic ineptness. Now thieves on the prowl for
mobile rigs know exactly which vehicles to target for a guaranteed
payoff. BTW, I also learned while researching details on...
This tutorial should be useful both as
an introduction to
amplifiers and for learning more details on them. We believe that even people
already having a substantial experience with fiber amplifiers will find it helpful
for deepening the understanding. The focus is on the underlying physics and the
resulting technical consequences; we do not simply treat a fiber amplifier as a
“black box”, but rather look inside. By RP Photonics Consulting GmbH.
years ago, Mozilla published an add-on tool called Collusion for monitoring
which websites were tracking your movements around the Internet. A follow-on app
Lightbeam, with even greater power, has been released: "Shining a spotlight
on online data tracking to help people understand the Web around them." As with
Collusion, Lightbeam gives you a picture of all the websites that are notified of
your presence on your targeted website. For instance, when you evaluate RF Cafe
using Lightbeam, you will discover that Google and DoubleClick (a Google subsidiary)
are notified in order to serve pay-per-click banner advertisements. I depend on
them to generate revenue for putting food on my table and a roof over my head. To
be honest, I have no idea what happens after Google checks in, other than being
fairly confident that the NSA is also notified as they are for every click, e-mail,
or phone call you make anywhere...
crossword puzzle was constructed specially for the good folks
in the engineering department of Brigham Young University (BYU). Event planner J.M.
wrote to request the use of a crossword, and in response I created one for them.
If you have a similar need, I will be glad to do the same for your group if I have
the time. Enjoy.
Orbel Corp. is the leading designer and manufacturer of
RF Shielding and EMI/RFI Isolation
Products for printed circuit boards and electronic enclosures. Orbel also specializes
in thin gauge photo etched metal parts and precision metal stampings made from a
wide variety of material options. We manage every aspect of metal stamping
from design, prototyping, short to medium runs and high volume stamping.
Spartant has developed a
new line of wideband
RF signal generators that have a USB interface. Their initial products include
two models: 25-6000 MHz and 25-3000 MHz, both featuring USB for control
/ power and both having a +13 dBm maximum output power with phase noise
of -106 dBc/Hz @100 kHz offset @250-1000 MHz. As with most USB test
instruments, the size is kept small (about the size of a deck of cards) by having
the user interface reside in software installed on the user's computer. An
Ethernet interface will be available in the near future.
Spartant is a
3dea Technologies company.
today's throw-away society, most people would never consider attempting to
repair a speaker if it were to develop a tear or a puncture. Why
should you bother when a replacement is so inexpensive? Well, there are several
reasons you might want to affect the repair yourself. First, the speaker might be
integrated into the system in such a manner that replacing it would be difficult
or even impossible. Second, some speakers are actually pretty darn expensive, especially
large diameter models and high quality models regardless of size. Third, a replacement
might not be available, as with a vintage radio or television. Fourth, maybe you
just want the challenge and satisfaction of repairing the speaker rather than adding
its bulk to a landfill...
Empower is pleased to be once again conducting
a "live" demonstration of an ultra broadband (20 to 1000 MHz), high power (1 kW
CW) amplifier platform
which is housed in an industry leading 5U chassis. The fact that we are controlling
this amplifier through a wireless connection and highlighting diagnostics and remote
control features through an iPad is equally impressive and, we believe, also industry
leading. Our live demonstrations throughout 2013 have been well received and, for
us, a serious validation of the next generation amplifier platforms we have designed
everythingRF has issued a newsletter highlighting some of the new items introduced
European Microwave Week. It is the largest event for the RF & Microwave
Industry in Europe. This year, 2013, it was held in Nuremberg, Germany from the
6-11 October. There were over 200 companies that took part in the exhibition.
JFW Industries is a world leader in designing and manufacturing of
passive RF components and application specific
test systems. These components include attenuators, RF switches, and specialized
test systems for use in the cellular, telecom, OEM test equipment, medical, automotive,
defense, and automated test systems markets. Application specific designs are the
cornerstone of JFW's continuous technical advances in RF components
technology and measuring techniques advance, the time eventually comes when continuing
to use old methods not only doesn't make sense, but can actually harm your reputation
by providing data that cannot be duplicated by customers who long ago adopted the
new ways. Orwill Hawkins, of LadyBug Technologies, has written a white paper describing
how to make accurate, repeatable peak and
pulse power measurements on waveforms using the precision of modern
instruments that provide a graphical view of the entity being investigated. USB
power meters provide an inexpensive means of obtaining high quality measurements
and the benefits of a graphical display environment (on your computer) at a relatively
low cost. I particularly like the use of the word 'mesial' in describing the midpoint
of a pulse's rising and falling edges.
Cahak, of Sunshine Design Engineering Services, has published yet another paper
in his series on making RF test measurements. This article will cover a recent test
experience that utilized some thinking about the test fixture, the bias requirements
and the device mounting and special calibration offsets needed to
de-embed the test fixture response from the device response within
the test fixture. The device also had to have bias on several ports simultaneously.
We had to establish a "reference plane" within the fixture, from which we can use
the Vector Network Analyzer's Port Extension or Phase Offset to dial out the distance
from our 1 port calibration reference plane to the point of short reference within
the fixture. With this phase offset compensation we can then measure the device
capacitance of the part...
AWR Corporation has launched a fully redesigned
AWR.TV portal directly from within
its main website framework to enhance the viewing experience of AWR’s hundreds of
demos and tutorial videos. The new AWR.TV platform now supports multiple platforms
for ready viewing on mobile devices such as iPads, iPhones, and Android handsets/tablets.
Recently added additions to the AWR.TV platform include AWR’s nine MicroApps presentations
from IMS 2013.
car is parked in a dark remote spot it is better to do the job where the car is.
This is because auto burglary is a lesser crime than stealing the whole damn car."
That remark was made by a 'former' thief who ostensibly gave up a life of crime
after spending nearly two decades in the slammer for various infractions of the
law. One of his specialties was breaking into cars to
steal radios - AM, FM, CB, Ham, or whatever was available. Mr. X
volunteered his insight for the benefit of QST readers who might want to take proactive
steps to help minimize the chance of being a victim.
Your source for RF Front Ends, transceivers
and amplifier systems that just plain work! Solutions for integrating high performance
HPAs into sophisticated RF subsystems and systems without sacrificing efficiency
and linearity. Please remember that DCH Systems merged with Triad RF Systems earlier
Skyworks Solutions announced that its industry leading wireless connectivity
FEMs are being leveraged by Broadcom for use in several of the company’s
5G WiFi solutions, enabling some of the fastest download speeds available in
access points, routers, DSL/cable gateways, PCs, smartphones and tablets.
Skyworks' complete 2.4 and 5 GHz 802.11a/g/n/ac solutions integrate the power amplifier,
filter, power detector, T/R switch, diplexer and associated matching in an ultra-compact
form factor, delivering all the essential functionality from the output of the SOC
to the antenna.
During the Golden Age of Radio (admittedly
a subjective term), electronics innovators were generally as likely to be hobbyists
(amateurs) as they were to be professionals with college degrees. In fact, according
to this open letter from Eugene F. McDonald, president of
Zenith Radio Corporation, in 1939, his company recognized the
fact that most of their best ideas came from amateur radio operators, and that their
engineering staff was populated overwhelmingly with Hams. Accordingly, the letter
was a solicitation to amateurs to submit their ideas to the company to give designers
not just valuable technical information gleaned from real-world experimentation
(aka the School of Hard Knocks) but also insight into what type of equipment the
Ham world would like to have made available for sale. Wouldn't it be great to still
see the foundational electronics brands...
OK, I admit that the
Hams in Space organizational patch
caught my eye and that's why I'm writing about it. Their little ploy worked on me
mainly because of its vintage design motif, but I'll be honest and admit there might
have been another reason as well. "Hams In Space is one of the KD0HKD.COM
Satellite Web Sites where you can learn how the Hams in Space Team can
come to your Amateur Radio Club Meeting, Hamfest, or Event to provide a presentation
on FM Amateur Radio Satellites!"
PMI Model No.
is a high speed, solid state, single pole single throw switch capable of switching
within 20 ns. The frequency range is 9.25 GHz (±30 MHz) with >90 dB
Visio is still
a mainstay for generating Office-compatible engineering block diagrams and schematics.
Its ability to be programmed for automation makes it even more valuable to the code-writing
Microsoft Visio 2003 Inside Out covers all the ins and outs that
you'll need to know to exploit its powers and to learn clever tricks for usage.
"This supremely organized reference packs hundreds of timesaving solutions, troubleshooting
tips, and workarounds all in concise, fast-answer format. It’s all muscle and no
fluff. Discover the best and fastest ways to perform everyday tasks, and challenge
yourself to new levels of Visio mastery!"
If you happen to be a fan
of the M*A*S*H television series from the 1970s, then undoubtedly you are familiar
with Corporal Maxwell Q. Klinger's multiple mentions of his old neighborhood of
Toledo, Ohio haunts - some manufactured and some real. His Toledo Mud Hens ball
team, for instance, is real. Uncle Abdul (Klinger is of Lebanese-American descent)
and his original wife Laverne Esposito (from the Hungarian side of Toledo) were
obviously fictional; however, it was because of Laverne that Klinger was introduced
Tony Packo's Cafe - a real place. The Hungarian style hot dogs
from Tony Packo's were tops according to Max. In fact, his mention on the television
show launched Tony Packo's to stardom and to being a highly prized tourist destination.
On Feb. 24, 1976, Jamie Farr (Klinger) put Tony Packo's on the map...
Palmer has a good piece on the Design News website titled "How to
Be a 'Doctor of Engineering' Without Going to Grad School" about how, according
to input from his son who is in medical school, the diagnosis technique being taught
to aspiring doctors is similar to the troubleshooting technique used by (in Dave's
case) mechanical engineers to get to the root of problems that are reported by customers.
Doctors, at least during their training phase, use a four-step process termed "differential
diagnosis." The doctor first notes symptoms and medical history, then considers
possible causes for the malady, then prioritizes the list according to likelihood,
and finally tests his conclusions by applying diagnosis and curative techniques.
The parallel to electronic as well as mechanical troubleshooting...
has hit a new low in the last few months. I have been noticing that every time I
use the Firefox browser that
are constantly popping up as the cursor is moved around the screen - even on
the RF Cafe website -- which does not have and never has had popup ads. The screen
capture below shows what I was seeing on my own website (RF Cafe)! I am NOT responsible
for any popups that you might get, and neither are any of my advertisers. A Google
search about the issue turned up many complaints about the same type of thing, primarily
on Firefox. It turns out that an add-in, which must have been installed stealthily
with an upgrade, was responsible. I don't visit questionable websites, so there
is little chance it was picked up in that manner unless...
RP Photonics Consulting
GmbH has published a tutorial "that can serve as an introduction to fiber optics;
i.e., for learning
basic of fiber optics, but it also helps to improve the understanding for people
who already have a substantial experience with optical fibers. The focus is on the
physics of wave propagation and its technical consequences. We do not go into mathematical
details, but rather try to create an intuitive understanding of the operation principles
– often by demonstrating certain effects with numerical simulations. The simulation
and design software RP Fiber Power of RP Photonics is an excellent tool for such
purposes and has been extensively used for this tutorial." [App Note
the mid-'90s, when downsizing was the dominant trend in business, Dilbert
took off." - Scott Adams
designs and manufactures the industry's widest range of
RF and microwave filters at frequencies
up to 40 GHz, as well as power dividers, directional couplers, and many other
product types. We specialize in standard and custom designs for commercial wireless,
public safety, satcom, and defense applications, and we can meet stringent military
if you listen to any of the
old-time radio broadcasts on the Internet, they are recorded version
of shows made long ago. However, back in the day those shows were first performed
live in front of microphones and recorded in a broadcast studio. With a cast of
two or three or even more, the actors would voice their lines with as much talent
and effort as those performing for movies. The crew usually included a group of
people responsible for creating background sound effects like horses running, car
horns tooting, airplanes buzzing by, and dogs barking. All was done real-time with
split-second timing required to pull it off and sound convincing. Radio audiences
were unaware of all the work required as they sat intently listening to the
Adventures of the Lone Ranger and The Shadow. Behind the scenes were
dozens of engineers and technicians tending local radio broadcasting equipment and
all-important telephone lines used for synchronizing...
accurate, reliable, and useful
measurements of RF power in the forward (transmission) and reverse
(reflection) directions requires careful selection of test devices and detection
equipment. LadyBug Technologies has produced a white paper describing a method for
performing reflection and transmission measurements using a power sensor and a directional
coupler. It includes a discussion on coupler directivity and impedance match as
a factor in measurement accuracy.
I create a crossword puzzle using a word list that I personally created and
added to during over a decade of making puzzles. All of the words are related to
engineering, science, mathematics, chemistry, astronomy, etc. There are no numbnut
clues about movie stars or clothing designers. Enjoy.
has been commonly used in capacitors since long before I came on the electronics
scene. Its widespread use in electronic and electrical components was first adopted
in Europe in the 1920s, and then later became popular in the U.S. where scientists
improved its characteristics and lowered its cost to where it could be found just
about anywhere current flowed. In its present form, polystyrene can be easily bent,
cut, turned, polished, melted, drilled and tapped - truly a versatile material.
This article provides a brief introduction to polystyrene.
circuits seem simple enough intuitively, at least for simple systems. It is
easy, though, for someone not comfortable with algebraic manipulations to arrive
at the wrong conclusion for how a given feedback constant figures into the calculation.
Such was the case with an article published in the ARRL's QST magazine,
when many readers wrote to the author accusing him of making an erroneous claim
regarding using feedback to cancel out an unwanted harmonic in an amplifier. The
criticism turned out being justified. Here is a statement of the error and an explanation
of the proper approach which was printed a couple months later.
The FCC (Federal Communications Commission) has
a very useful website set up for finding information about who owns spectrum licenses
around the country, and what spectrum is available in your county. The
Spectrum Dashboard has four
primary methods for searching spectrum in the United States. You can use the dashboard
to find out how spectrum is being used and by whom. There is an interactive allocation
chart like the big wall charts that the magazines used to give away, only the nice
thing about this one is that it never goes out of date. Of course the flip side
is that if you wanted to research the historical band allocations you would need
to look elsewhere. From the main page you may perform the following searches.
Be aware that the map does not display where the frequencies are licensed or being