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A Winding Machine
There are still a lot of people who wind their
own coils, whether it be for an amateur radio rig or for work in the lab. I know
I've wound many a coil around a drill bit or wooden dowel. This simple
coil winding machine that appeared in a 1931 edition of QST magazine would be
a handy addition to anyone's bag of tricks, especially if find yourself winding
single-layer coils that have a fixed space between the windings. The home stores
like Lowes and Home Depot sell small pieces of oak that would be perfect for this
kind of project. A little stain and a coat of varnish would give it a real vintage
look. Use your soldering iron to burn your name onto the base.
PMI Intros 10 GHz Integrated
Dielectric Resonator Oscillator
PMI Model No. PIA-10G-CD-1 is a
Integrated, Dielectric Resonator Oscillator (DRO) Module with 3 outputs, each
having a 0-360 degree analog controlled, variable phase shifter and 0-10 dB
analog controlled, variable output control capability on each output. Provides low
harmonic output of -50 dBc typical and output power of +19 dBm typical. ±15 VDC,
6.25” x 2.5” x 1.0” package. Other frequency ranges available.
"So few autopsies are being done now that
many medical students get out of school never having seen one." - Gregory Davis,
U. Kentucky College of Medicine, November 2012
Scientific American. That's as ridiculous as an EE student graduating
without ever having to learn to troubleshoot circuits. Oh, wait...
MECA Electronics Intros Line
of Unequal Power Splitters
MECA Electronics' new line of
unequal power splitters consists
of six models offering a 2, 3, 4, 6, 8, or 10:1 signal-split ratio respectively,
over 698-2700 MHz (Cellular, PCS, AWS, and BRS/EBS frequencies) and feature
low PIM ratings – (better than -150 dBc.), with ultra-low VSWR and minimal
coupling variation over the entire frequency band. They easily handle high power
levels of 300 W (CW) and have an operational temperature range of -55°C to
+85°C. As with all MECA products, they are MADE IN THE USA and
are offered with a standard 36 month warranty.
NuWaves Engineering Adds to
Its Int'l Reseller Network
NuWaves Engineering, a Radio
Frequency (RF) and Embedded Systems solutions provider, announced today that the
company has increased its international presence by adding authorized resellers
in Europe, Southeast Asia, and the Middle East. These new partners will represent
the company's high-performance module-level RF products and engineering design services.
Entry Level RF Applications
Nitronex LLC has new opportunity for a junior
or entry level engineer that is looking to aid in the applications engineering of
discrete and MMIC RF and Microwave power products on Nitronex's unique GaN-on-Silicon
process. You'll be driving the post production applications development of MMICs
and discrete devices that span from UHF to X-Band. Nitronex is a quickly growing
company that requires driven, talented individuals to bring new technologies to
market that will enable devices to operate to X-band and as high as 65V. Candidates
must hold a BSEE and a demonstrated interest in RF electronics, including hobbyist/enthusiast
experience, senior design work, elective coursework etc. and a desire to work in
a fast paced, startup environment. Alternatively, candidates can possess an MSEE
with relevant coursework/thesis in RF and Wireless design.
Webinar: Precise Cable
and Antenna Measurements
Techniques for Precise Cable and Antenna Measurements
in the Field Date, by Agilent and TESSCO, Wednesday, October 24, 1:00 PM ET.
This webcast introduces measurement and calibration techniques for cable and antenna
testing (CAT) using the new Agilent FieldFox handheld microwave analyzers. We will
discuss a variety of measurements such as cable insertion loss, return loss, VSWR
and Distance-to-Fault (DTF) testing. Antenna measurements are also discussed and
several examples of return loss and antenna-to-antenna isolation will be provided.
Les Fantômes de la
Seconde Guerre Mondiale
These photos are the result of superimposing
images of scenes during
World War II on top of modern images of the same locations in
France today. It was a time when
Americans were not
asked for passports when entering the country by sea and air. Historical expert
Jo Teeuwisse, from Amsterdam, began the project after finding 300 old negatives
at a flea market in her home city depicting familiar places in a very different
Scientist Wrong = Jail
Bureaucrat Wrong = Promotion
Many of us have joked about wishing we had
a job like the weatherman's since it didn't seem to mater how often or egregiously
he was wrong, he got to keep his job. No
ever went to jail for failing to foretell the ultimate effects of a storm system,
nor an avalanche expert for not predicting exactly where and when a snow pack would
leave its mountain mooring. It would be unreasonable to expect that level of prognostication
from practitioners of the scientific method, right? Not anymore. A new precedent
has just been set by an Italian court that found six earthquake experts guilty of manslaughter for not properly
warning of the 2009 earthquake in the city of L'Aquila that killed 308 people. They
can kiss freedom goodbye for 6 years (maybe less with
good behavior). So, bureaucrats who routinely fail to predict untold numbers
of financial and civil catastrophes that have directly or indirectly caused loss
of life will continue to get promotions and pay raises while scientists who fail
to predict a *&%$@ natural phenomenon now go to jail. Congratulations, Italy,
you have set an example that will soon be coming to a country near the rest of us.
Copper Mountain Technologies
Featured in MW&RF
Copper Mountain Technologies'
website declares, "Virtual Instruments. Real Performance. Real Value." What that
means is their line of "virtual" instruments are as "real" as an all-in-one test
box. CMT's network analyzers have a USB interface to your computer, where supplied
software provides the user interface and number crunching power. Portability and
price is a huge benefit. Their 300 kHz - 1.2 GHz model starts at just
$2.5k. Going to 8 GHz costs you $17k.
Microwaves & RF magazine did a nice feature article on them.
The origin of the company name, detailed in the column, is kinda cool, too.
- A Menace
J.K. Bach (not
Johann S.) was amazingly prescient in 1944 with the specific types of RF-based
devices that would come to be common place in our modern world. Dig this: "Radar
can even be applied to the home, as a burglar-alarm, for example, or to detect obstructions
on the cellar steps. Electronic devices will find many other uses as high-frequency
paint-dryers, veneer-gluers, and even cordless permanent-waving machines for the
ladies. Garage-door openers and other remote-control devices are not only possible
but practical. Then there are certain to be other applications such as personal
pedestrian telephones, two-way wrist-radios and nursery baby-cry announcing systems."
Nostradamus' divination record might not even be that good. His tongue-in-cheek
thesis of ubiquitous RF interference due to the presence of Ham radio operators
is not far off either, although the accused "menace" would have to be extended to
include all the many varied emissive devices being used by tech-ladened pedestrians.
RFMD Intros Control
Components for Cable Apps
RFMD today unveiled two new CATV control components,
in conjunction with the SCTE Cable-TEC Expo, in Orlando, FL. The new components
RFSA2654, a 75-ohm broadband digital step attenuator, and the
RFSW1012, a high power handling single-pole, double-throw switch
Microwave Office Designs
"Right the First Time"
Amplifier Technology, Ltd., (ATL) a provider of leading-edge
RF power amplifiers (PAs) for defense, commercial, industrial, scientific, and medical
applications, used a unique combination of AWR's Microwave Office RF/microwave design
suite and AMPSA's MultiMatch Amplifier Design Wizard to design a complex multi-octave
bandwidth, high power, high efficiency PA.
Please Thank Hittite
Microwave for Their Support
Hittite Microwave manufactures
ICs, modules, subsystems &
for technically demanding digital, RF, microwave and millimeter wave applications
covering DC to 110 GHz. The Company's standard and custom products apply analog,
digital & mixed-signal semiconductor technologies, which are used in a wide
variety of wireless / wired communication and sensor applications for automotive,
broadband, cellular infrastructure, fiber optics, microwave & millimeter wave
Analog Engineering Theme
Crossword for 10/21/2012
For the sake of avid cruciverbalists, each
week I create a new
puzzle that has a theme related to engineering, mathematics, chemistry, physics,
and other technical words. You will never be asked the name of a movie star unless
he/she was involved in a technical endeavor (e.g., Hedy
Calculus of Negligence
aka "Hand Rule"
Whilst reading an article on legal liability,
I ran across a reference to the
Rule, formulated by Judge Billings Learned Hand
(yes, that was his given name). Hand, who studied
both philosophy and law, was a judge credited with a keen sense of honor and fair
play as applied, in conjunction with Constitutional principles, to such as patents,
torts, admiralty law, and antitrust law. The
Hand Rule was born
out of a trial where an improperly secured barge escaped its moorings and caused
damage to other boats. Per the Hand Rule:
"[T]he owner's duty, as in
other similar situations, to provide against resulting injuries is a function of
three variables: (1) The probability that she will break away; (2) the gravity of
the resulting injury, if she does; (3) the burden of adequate precautions. In mathematical
terms: B < PL, where B is the cost (burden)
of taking precautions, and P is the probability of loss, and L is the gravity of
loss. Simply stated, negligence is ruled if the effort required to prevent an event
is less than the likelihood that the event will occur, multiplied by the severity
of the loss. This, of course, is all subjective, which is why he who hires the lawyer
best able to define values for B, P, and L wins the case. I propose an alternate
name for it: Fuzzy Law.
RFMD Unveils GaN-Based
Amps for CATV Applications
RF Micro Devices unveiled multiple leading-edge
GaN-based CATV amplifiers, in conjunction with the SCTE Cable-TEC Expo in Orlando,
FL. The new CATV amplifiers include the
RFPD2940 – a best-in-class, high-power GaN-based CATV power-doubler
amplifier, as well as a new family of GaN-based push-pull CATV amplifiers, led by
Many Thanks to SigaTek
for Their Support
SigaTek microwave specializes in
high quality, high frequency microwave communication components up to 60 GHz.
As a pioneer supplier of microwave
RF components, the main products include directional couplers, bias tees networks,
power dividers / combiners, 3 dB hybrids 90° and 180°, microwave mixers, frequency
doublers, load terminations, and coaxial connectors and adapters.
Bandwidths, by Jon Titus
Jon Titus is a lot like Bob Pease - only without
the scraggly beard - when it comes to
Along with having a PhD and being the former editor of EDN and Test &
Measurement magazines, Jon has an innate knowledge of circuit theory and is
very good at presenting complex information to lesser beings like myownself[sic].
Most of us want to be like them when we grow up. One big difference between Jon
and Bob, though, is that Jon does not eschew the use of computers. I think Mr. Pease
might have been OK with the ENIAC, but once IBM introduced the XT, it surely dumbed
down every future engineer from that point forward according to his oft-repeated
denouncements of anything with a silicon-based processor. Fortunately for Bob -
and for those of us to whom he addressed - he didn't need a computer for most tasks.
This short column from Jon Titus titled "Undersampling Changes Bandwidths" is a great primer on how undersampling
works. In a Pease-esque way, Jon uses hand-drawn sketches to illustrate the sampling
Quiz: LCP for Microwave
Packages and Modules
This quiz is based on the information presented
in LCP for
Microwave Packages and Modules, by Anh-Vu H. Pham, Morgan J. Chen, and Kunia
Aihara. Note: Some of the books used for quizzes are available as prizes in the
monthly RF Cafe Giveaway.
Thanks to Test Equipment
Connection for Support!
Connection handles sales, rentals and leasing of refurbished electronic test and
measurement equipment to the R&D, manufacturing and quality assurance industries.
All major lines including Agilent, Tektronix, Anritsu, Rohde & Schwarz, Advantest
A Surprising Message
from Scott Adams
The creator of Dilbert, Dogbert, Catbert,
Wally, Alice, Asok, and the pointy-haired boss has just endorsed a presidential
candidate based on a medical marijuana prosecution. Keep in mind that
Scott Adams suffered a rather
severe nervous system malady in the middle of the last decade. Although I cannot
find anything for certain about whether he uses it himself, there is a good chance
that he does. Adams,
you might recall, lost his ability to speak and to draw for a couple years, then
miraculously gained back most of his functionality. The Dilbert cartoon rarely ventures
overtly into political themes, so it will be interesting to see if a strip on the
subject appears between now and election day.
An Old Spark Soliloquizes
If it has been a while since you read a story
with terms and phrases like "splinters of galena," "the day of the tuning coil that
stretched from the front bedroom to the back library; or from the attic to the cellar,"
and "Ether God," then this article from the December 1931 edition of QST is for
by the way, is a semiconductor with a bandgap of about 0.4 eV that was used
as the crystal in crystal radio sets. It was used as a point-contact diode along
with a safety pin or similar sharp wire, commonly known as a "cat's whisker".
Please Welcome DCH Systems
as a New Supporter
DCH Systems is engaged in the design and manufacture
of RF power amplifiers and systems.
Their mission is to provide advanced, highly linear, and efficient RF amplification
solutions for customers in the aerospace / defense, telecommunications, and science
communities. DCH Systems' core competency is the ability to design and manufacture
RFPAs utilizing pre-distortion techniques, and possesses the expertise to implement
the high-complexity analog and digital circuitry to produce user-friendly, reliable
RFPA products that are suited for both low and high volume manufacture.
How to Talk to Non-Hams
Here is a pretty funny story that, although
it is fictional, it could easily have really happened. I'm not much of a party-goer,
but base on what little experience I've had at social functions and the stereotypical
behavior often portrayed in movies, the author's scenario likely actually did occur.
Maybe he exaggerates just a bit, though. The follow-up situation would be a great
gag to play on someone if you ever get the chance. It probably would not be hard
to get people to fall for it.
Job Hunting Articles/Tips
When a Job Offer is
Put on Hold
How Much is an
Top 5 Personality Traits
Employers Hire Most
Why Engineers Need
Critical Thinking Skills
- Everyone's an Entrepreneur!
Do New Job Tests Foster
5 Threats to Your Job-
RFMD® Intros 915 MHz ISM
Tx/Rx Module w/Diversity Sw.
RFFM6901 is a single-chip front end module (FEM) for applications
in the 868/915 MHz ISM Band. The RFFM6901 addresses the need for aggressive
size reduction for typical portable equipment RF front end design and greatly reduces
the number of components outside of the core chipset, thus minimizing the footprint
and assembly cost of the overall solution.
High Frequency Electronics
October 2012 Articles
by S. Kumar, K. Story,
R. Kielmeyer, T. Lodhi,
and I. Hardcastle, RFMD
(p.22) S. Akamatsu,
S. Muir, L. Dunleavy
Microwave Journal Articles
Dynamic Range for
by Brian Avenell
New Tile Structure for
Microwave Modules Using
J. Moon, S. Yun, C. Ahn,
LTE Downlink Transmitter
Simulation Using MATLAB,
by J. Pierzchlewski,
Webinar: RF Recording to
Resolve Interference Problems
Using RF Recording
Techniques to Resolve Interference Problems, Thursday, October 18, 2:00 pm EDT.
This webcast discusses the problems associated with system operation in a cluttered
environment, and RF recording techniques that can be used to capture minutes or
hours of data for subsequent analysis.
GreenPeak ZigBee Success
Using AWR Software
Microwave Office/AXIEM software,
GreenPeak was able to successfully perform RF board analysis, validation, and optimization
for best RF performance, certification margin, and production yield, while at the
same time cutting design iterations down to one or two when integrating its custom
design into the ZigBee remote control device.
"Men are dressing for the office far more seriously,
in an effort to maintain a level of job security" -- Steven Faerm, Parsons the New
School for Design, in OFA
Please Welcome Mayfield
Plastics as a New Supporter!
Mayfield Plastics provides in-house thermoforming
and twin sheet forming processes that can achieve the look and feel of injection
molding without the expensive tooling charge. Pressure forming is able
to form details normally found only in injection molding. Thermoforming has many
advantages over the use of sheet metal, such as lower unit cost, lighter weight,
and enhanced appearance. Radomes, device enclosures, and control panels are
among possible applications.
Please Visit IPP to Thank
Them for Their Sponsorship
IPP is a manufacturer of
RF passive components - 90° Couplers, directional couplers, RF resistors and terminations.
Connectorized, surface mount. Custom designs are available.
Thanks to Antenna Factor
for Long-Time Support
Antenna Factor, a division of Linx Technologies,
manufactures standard and custom antennas - monopole, dipole, embeddable, specialty,
dualband, GPS, fixed point, Yagi, evaluation systems, custom designs. Hole-mount
and magnetic bases available.
Anaconda Copper Mining
It's not often that you will see a full-page
ad promoting a particular element in the periodic table, but in 1950 that wasn't
the case. This advertisement for
Anaconda Copper Mining Company promoted the virtues of element number 29 - copper
(Cu , from the Latin "cuprum"). Aluminum and iron were other popular topics of advertising.
If you do a search on the history of Anaconda, which is today owned by the Atlantic
Richfield Company (ARCO), what dominates is the harm done to workers and to the
environment. The short video below is one of the less vicious reports on the company's
operations in Butte, Montana and in Chile.
As with many forms of mining back in the day, miners were subject to very hazardous
conditions, lived in company towns in company houses, sent their kids to company
schools, and bought their groceries at company stores. It was a rough life, and
we who enjoy the abundant freedoms and conveniences availed to us today owe...
GE "Black-Daylight" TV Ad
in 1950 Saturday Evening Post
You might think I tend to dwell too much on
the past because of all the articles posted and references to vintage electronics
companies and their employees. Maybe I do. My motivation is two-fold. First, I enjoy
waxing nostalgic over the simpler, less crowded days of yore that were the 1920s
through 1940s, and even into the 1950s. Things were not ideal by any means, but
America was a thriving bastion of national innovation and manufacturing. A "wow"
factor surrounded new discoveries and deserving heroes were created. Our friends
as well as our enemies were well-defined and our schools put more effort into teaching
literature, mathematics, and science than into what "rights" could be demanded without
earning them. Second, which really follows from the first, is that I hope by reminding
people of, or in some cases - especially younger website visitors - introducing
for the first time, the fact that being a country that is fundamentally independent
Amateur Radio Stations
When the caption for a photograph in a 1931
article refers to an
motor, you can be sure you're looking at a really old motor. Indeed it does
look very old. Whenever I see vintage photos or films of electrical / electronic
apparati[sic] and operators, I always look for safety issues like no eye protection
while soldering or when using powered tools to fabricate enclosures, lack of protective
shields around electrical connections and mechanical drive mechanisms, wearing of
inappropriate clothing near rotating machinery, etc. In this case you can see a
very long, totally exposed drive belt running between that aforementioned antiquated
motor and DC generator that it drives (to power the transmitter). The author mentions
how the floor shook while it was running. I wonder if the filaments were shaken
enough to introduce the vibration frequency into the audio (mircophonics)? Ah, the
not quite so good old days.
AWR Announces Slate of
Activities during EuMW 2012
AWR Announces Slate of Activities during European Microwave
Week 2012. Highlights Include Software Demos in Booth #416 of AWR 2011 Product Portfolio
and Analyst™; AWR and Partners MicroApps; AWR/National Instruments Workshop; and
Customer Appreciation Event.
SNL Skit on iPhone 5 Issues
This is a hilarious spoof that
Live came up with for addressing the well-known issues with the new iPhone 5.
Christina Applegate plays the host to a panel of tech industry gurus and a "trap"
panel of Chinese iPhone 5 factory workers. "Tech Talk" faux representatives
from real-life entities CNET, Wired Magazine, and Gizmodo gripe about the funky
maps, "purple haze" from the camera, and how easily scratched the case is (these
are the top 3 complaints by users). After smarmily registering their complaints,
the hostess then presents employees from the iPhone 5 factory (Foxconn is never
mentioned by name) who proceed to sarcastically address each topic with responses
demonstrating how petty the whining is compared to their life's woes in China under
Communist rule. I won't give any more away; you'll have to watch it to get the full
effect of its humor.
Many Thanks for Backing by
evaluation kits and master development systems feature straightforward hardware
configuration and clear documentation. Linx products make it simple for engineers
and hobbyists to integrate wireless features without the hassle and expense of engineering
RF functionality from scratch.
These Fuses Melt in Water
Sherlock Ohms is a regular feature of Design
News that presents submissions from readers about troubleshooting challenges and
how they were solved. This one is titled "These Fuses Melt in Water."
Free IEEE-USA eBook
Writing for Success—An Engineer's Guide,
Volume 1: Designing for Success. In the first book of this four-book series,
award-winning author Tom Moran presents writing from an engineer's perspective:
looking at comparisons between the steps that lead to good engineering practice,
and those that result in writing excellence. Free download for members through October
Felix Baumgartner Sets
Jump Height & Speed Record
On Sunday, October 14, 2012, Austrian parachutist
Felix Baumgartner stepped
out of his balloon-borne pressurized capsule at a record-setting height of 128,000
feet and became the first man to break the sound barrier during free fall
(1.24 Mach). The previous record had been set
way back in 1960 by Joe Kittinger, who handled communications with Felix during
his stunt. Felix missed breaking Joe's free fall duration record by a mere 6 seconds.
sponsored the Stratos project.
Please Thank Apex Wireless
for Its Continued Support
Since 1985, Apex Wireless has offered consulting,
engineering, and design services focusing on high-performance, cost-optimized products
that employ wireless RF transmitters, receivers, and transceivers. To complement
our RF design expertise, we work with local experts in DSP, ultra low power design,
packaging, certification, and manufacturing.
Thanks to Alliance Test
Equipment for Support!
Sales, rentals and
leasing of refurbished electronic test and measurement equipment to the R&D,
manufacturing and quality assurance industries. Alliance Test Equipment carries
all major manufacturers' equipment.
Parallel Water Filters Increase
Flow Like Parallel Resistors
The municipal water supply here in Millcreek,
Pennsylvania (next to Erie), leaves a bad taste
in my mouth - literally. It's hard to make a good cup of coffee with bad water,
so I decided to install a high quality water filter. The water pressure for the
supply line is pretty good, so I figured that pressure reduction due to the filter's
presence would not be too bad. I was wrong. This was no surprise since I have installed
the same type of filters in other houses. After about two years of having about
half the water flow from the cold water faucet as from the hot, I decided to do
something about it. Changing the filter helped a bit, but not much. So, I figured
it was time to test the theory of
equivalency between water pressure and electromotive force pressure
(voltage) when applied through parallel resistances.
In this case the resistance is provided by the water filters and the pressure is
provided by the town's water supply...
Jump in Process Live
Watch Felix Baumgartner make his ascent in the
Red Bull Stratos capsule
to 23 miles above Earth, then do a free fall that could make him the first skydiver
to break the sound barrier. SUCCESS!!!