Homepage Archive #10

These archive pages are provided in order to make it easier for you to find items that you remember seeing on the RF Cafe homepage. Of course probably the easiest way to find anything on the website is to use the "Search RF Cafe" box at the top of every page. About RF Cafe.

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Amateur Radio Astronomy

in QST Magazine

Amateur Radio Astronomy Articles in QST - RF CafeQST is the official publication of the Amateur Radio Relay League (ARRL), the world's oldest and largest organization for Ham radio enthusiasts. Many amateur radio operators also have an interest in astronomy and as such, occasionally articles appear covering topics on amateur radio astronomy. There are also quite a few articles dealing indirectly with aspects of astronomy such as Earth-Moon-Earth (EME) communications where signals are bounced off the moon's surface in order to facilitate transmission (although it is really more of a hobby achievement). The October 2012 edition of QST had an article entitled, "Those Mysterious Signals*," which discusses galactic noise in the 10-meter band. Arch Doty (W7ACD) writes about the low-level background noise that is persistent in the high frequency (HF) bands. At HF, Cygnus A and Cassiopeia A are major sources of cosmic noise, for example. Low level signals come from pulsars...

High Frequency Electronics

Articles Update

November 2012 High Frequency Electronics Magazine Articles Available - RF CafeThe November edition of HFE is now online for the non-tree-killers and/or the technophile-cum-e-reader types amongst us.

Wireless Sensors without Batteries, byAli Abedi

Benefits of Mixed Dielectrics When Used for High-Frequency PCB Applications, by John Coonrod

Pasternack Expands Line of

High Power Attenuators

Pasternack Enterprises Expands Line of High Power Attenuators - RF CafePasternack Enterprises introduces their new line of 100 Watt high power attenuators. This new line of attenuators is perfect for applications requiring reliable and consistent frequency levels up to 6 GHz. Pasternack Enterprises' line of high power RF attenuators operate from DC to 6 GHz and have an average power rating of 100 Watts, with peak power handling capabilities of 2,000 Watts from -55 to +125° C. High power fixed attenuators from Pasternack are constructed with lightweight, but strong anodized aluminum heatsink bodies and can be ordered with passivated stainless steel SMA, TNC and N connectors, and silver plated brass 7/16 DIN connectors. Pasternack's high power coax attenuators are manufactured with large cooling fins.

Sherlock Ohms: Strange

Case of the High VSWRs

Sherlock Ohms: Strange Case of the High VSWRs - RF CafeSherlock 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 "Strange Case of the High VSWRs" The author discovers test equipment setup issues.

Triad RF GaAs RF PA Module

Meets LTE Requirements

Triad RF Systems GaAs RF Power Amplifier Module Meets LTE Requirements - RF CafeTriad RF Systems introduced the Model TA1011, a compact GaAs RF power amplifier module that delivers over 20 W peak power from 1700 to 2000 MHz (other bands available) and is well suited for both wireless communications and CW applications including radar, electronic warfare, medical, and measurement systems. The TA10111 incorporates linear circuits that raise the OIP3 to +60 dBm which allows this small amplifier to produce over 4 Watts of linear, 10 MHz LTE. It has gain of 50 dB, return loss of -14 dB (1.5:1 VSWR), rise and fall times of less than 1 µs, accepts a maximum RF input of +10 dBm and has a 30 dB RF Sample Port.

PMI Intros 1.0 to 26.5 GHz

Ultrabroadband Amplifier

PMI Intros 1.0 to 26.5 GHz Ultrabroadband Amplifier - RF CafePMI Model No. PEC-14-127-8-12-SFF-1 is an ultra-broadband amplifier that operates over the frequency range of 1.0 to 26.5 GHz. This model provides gain of 13 to 17 dB and has a maximum gain flatness of ±1.5 dB. The maximum noise figure is 5.5 dB from 1.0 to 20.0 GHZ and 6.0dB from 20.0 to 26.5GHz. This amplifier can handle input power levels up to +10 dBm with no damage and the Input IP3 is +3 dBm minimum.

Hytron Corporation Ad from

the June 1944 QST

Hytron Corporation Advertisement, June 1944 QST - RF CafeHere is an advertisement for Hytron Corporation that I scanned from page 83 of my copy of the June 1944 QST magazine. Hytron was a manufacturer of electron tubes. "So Many Owe So Much To So Few," reds the title line. That is a paraphrase of Winston Churchill's famous statement during World War II, "Never in the field of human conflict was so much owed by so many to so few." That was in August 21, 1940, more than a year before the U.S. entered the war. Perhaps of greater interest to RF Cafe visitors are the next lines: "In peace, the Nation's debt to the radio amateur was great. During hurricanes, floods, and other disasters, he sprang forward with emergency communications. His endless hours of patient experimentations - particularly on the high and ultrahigh  frequencies - helped open up, as if by magic, whole new segments of the radio spectrum. Traffic enthusiasts surprised the people with unselfish service; DX hounds fostered international goodwill."

Webinar: Antenna Simulation

with COMSOL Multiphysics

Webinar: Introduction to Antenna Simulation with COMSOL Multiphysics - RF CafeIntroduction to Antenna Simulation with COMSOL Multiphysics, Thursday, November 29, 2 PM ET. The COMSOL Multiphysics RF Module is well-suited for the modeling of antennas. In this webinar, a classical dipole antenna model will be built and solved from scratch. All of the key steps in the software will be addressed. More complex models will be introduced, and applicability in Multiphysics areas such as RF and tissue heating, as well as thermal drift and deformation modeling will be discussed.

Mayfield Plastics Releases

Thermoforming Whitepaper

Mayfield Plastics Releases Thermoforming Whitepaper - RF CafeMayfield Plastics has announced the release the “Introduction to Thermoforming and Vacuum Forming Whitepaper”. Mayfield constructed the guide because they realize that many people, including designers and engineers, do not completely understand the plastic forming process. Often confused with injection molding and rotational-molding, thermoforming processes are unique and have distinct differences for a variety of applications. Thermoforming produces custom plastic enclosures that are durable, cost-effective, high quality and aesthetically appealing while offering close tolerances, tight specifications and sharp detail.

AWR's Schedule of Activities

at MWE 2012

AWR’s Schedule of Activities at MWE 2012 - RF CafeAWR is offering an array of software demonstrations, lectures, and partner presentations at the Microwave Workshops and Exhibition 2012 (MWE2012) in Yokohama, Japan from November 28 through November 30. AWR's booth #A305 featured demonstrations of the AWR Design Environment include: Analyst for 3D EM analysis, Power amplifier design using digital predistortion for linearity improvement, High performance circuit envelope simulation ,Radar system simulation using Visual System Simulator™ (VSS) and comprehensive radar libraries, Antenna design using AXIEM®, Microwave Office™/AXIEM for PCB verification via ODB++, Matching circuit synthesis using iMatch and filer synthesis using iFilter.

Does America Have

a Scientist Shortage?

Does America Have a Scientist Shortage? - RF CafeNot according to Derek Lowe (aka 'The Contrarian'). In his October 2012 article that appeared in Discover magazine, Mr. Lowe cites the following statistics to support his assertion: Of 633e3 graduate-level students in science, engineering, and health fields in 2012, less than ¼ secure a tenure track academic job within 5 years of earning a Ph.D. Of 63e3 postdoc appointees in the same group, up 45% from 2000, many cannot find permanent employment. A 3% (doesn't seem like that much to me) decrease from 2006 to 2010 in federal non-defense R&D funding harms science-related job seekers. The overarching theme is that the problem is not a deficit of graduates, but a glut of high quality candidates for employers. He also published an article on the same topic earlier in the year titled, ".No, America Does NOT Need More Scientists and Engineers" It's a thing with him.

Thanks to Copper Mountain

Technologies for Support!

Copper Mountain Technologies is changing the way Vector Network Analyzers are incorporated in lab and production environments. The company's unique virtual VNAs deliver highly accurate measurements at half the cost of traditional VNAs. Leveraging breakthrough advances in RF technology, CMT's Planar VNAs provide high measurement accuracy, a wide dynamic range, a familiar UI and a broad variety of standard features. By developing VNAs that utilize external PCs, CMT offers users flexibility, portability, improved security and upgradeability.

U.S. Department of State Says

Spacesuits Are Weapons

U.S. Department of State Says Spacesuits Are Weapons - RF CafeWho would have guessed that you need the blessing of the U.S. Department of State if you want to make and sell spacesuits? Yep, spacesuits are classified as weapons since, by bureaucratic logic (yeah, a non sequitur), if you have the capability to attain a presence at an altitude that requires a spacesuit, you can be a strategic threat to the nation. Here is a story about a startup company in Brooklyn, NY, that found out the hard way about the spacesuit-weapon requirement. There is a rapidly growing demand for functional-yet-stylish spacesuits for safeguarding wealthy space tourists who will soon be blasting off to the top of Earth's atmosphere where space officially begins (at about 50 miles / 80 km). BTW, I tried finding the official policy on spacesuit production the Department of State website, but their search engine keeps failing - must be busy deleting files on the Benghazi massacre.

More November 2012 Magazine

Articles Available

More November 2012 Magazine Articles Available - RF CafeSome of the RF & microwave magazines have updated their online editions for November, so here are a few you might like to check out. A lot of the articles end up being way over my head in theoretical applications, so I tend to stick with practical stuff that most of us can use. You be your own judge, though.

Microwave Product Digest

Emerging RF Technologies for Smartphones and Connected Devices, by Ben Thomas, RFMD

Why Test Instrument Frequency Range Matters When Conducting Signal Integrity Measurements, by Bob Buxton

Just Under the Radar: Where Does It Go From Here?

Bob Pinato, MPD Editorial Advisor

Spectrum Analyzers Continue to Advance, by

Frost & Sullivan

Delco Radio Advertisement

from the June 1944 QST

Delco Radio Advertisement, June 1944 QST - RF CafeHere is an advertisement for Delco Radio that I scanned from page 77 of my copy of the June 1944 QST magazine. "What's Magic About Electrons?," is the question asked. Answer: "The magic about electrons is man's ingenuity in putting them to work. The magic about electrons is their promise of service in marvelous ways only hinted at in the last few years. Now harnessed for war, the science of electrons will later work to enrich the peace. Working in close cooperation with Army and Navy engineers, Delco Radio has applied its knowledge and skill in putting electronics actively and effectively into the fight for Victory. In Delco's laboratories, principles are explored and exploited; in Delco's engineering departments, designs are evolved to apply these principles; and on Delco's production line, complete equipment is manufactured with the speed  and skill that only a large manufacturer of precision radio instruments can bring to such work."

They Know Where You Are...

and What You Want

They know where you are and what you want... - RF CafeThe December 2012 edition of Scientific American has a short article discussing how much information not just Big Bro but also the Internet search engines has on you - both from a historical perspective and in real time. In the former case the purpose is for surveillance and exploitation for a blackmail motive if the need arises, and in the later case for exploitation with a profit motive since the need always arises. Your cellphone is a godsend to such amassers of personal data. As reported, services like PlaceIQ* and Skyhook† know that you are most likely to click on a smartphone advertisement if, based on your phone's location data, they discover you are sitting in a movie theater before the film starts rolling, if you are at home on a Sunday morning, or if you are in the middle of a lake fishing. That is when the ad services charge companies the highest fees for serving a clickable promo to your phone. With enough data, they can deduce your personal identity. Maybe that can be used to set up an ambush by a hacker who gets access to it. Nice, eh? You are soooo... predictable!

* Per their website, "PlaceIQ extracts context and meaning from location data and organizes this into actionable intelligence about a hyper local location."

† - “There's no part of society that's not going to use these data,” says Ted Morgan, CEO of Skyhook

Experts Face Fewer

Challenges in Court

Experts Face Fewer Challenges in Court, Survey Says - RF CafeExpert witnesses play a big role in most - if not all - of the court cases that get reported here on RF Cafe. IMS ExpertServices is a law firm specializing in expert witnesses. Every month or so they send me an article about specific court cases that could be of interest to my visitors. This particular installment is titled, "Experts Face Fewer Challenges in Court, Survey Says" and reports that after a decade of increases, in the year 2011 a large drop in the numbers of court challenges to expert witnesses' testimony has been observed. Surprisingly, nearly half of the experts' opinions were successfully challenged. The leading reason for dismissing expert testimony: lack of reliability. Who would've guessed that a person getting paid to advocate a point of view might not be the most credible client.

PMI Intros 5.3 to 6.0 GHz

Quadrature Coupler

PMI Intros 5.3 to 6.0 GHz Quadrature Coupler - RF CafePMI Model No. QC-5D3G6G is a quadrature coupler that operates over the frequency range of 5.3 to 6.0 GHz. This model provides low loss of 1 dB and an isolation of 18 dB minimum. The VSWR is 1.4:1 maximum into a 50 ohm impedance. The amplitude balance is ±0.7 dB maximum and the phase balance is ±5 degrees maximum.

Sherlock Ohms: Lightning

Knocks Out Aircraft Compass

Sherlock Ohms: Lightning Knocks out Aircraft Compass - RF CafeSherlock 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 "Lightning Knocks out Aircraft Compass." Lots of people have magnetization stories to tell, evidently.

Thanks for Pulsar Microwaves'

Continued Support

Pulsar Microwave is celebrating its 25th anniversary as a valued supplier of passive microwave components covering the frequency range of 10 kHz to 40 GHz with both narrow band and ultra-broadband products for the wireless communications markets. ISO and RoHS.

PMI Intros 1.4 to 2.4 GHz LNA

PMI Intros 1.4 to 2.4 GHz Low Noise Amplifier - RF CafePMI Model No. PE2-42-2G-2R0-15-SFF is a low-noise amplifier that operates over the frequency range of 1.4 to 2.4 GHz. This model provides gain of 42 dB minimum with a typical noise figure of 1.8 dB. The output power at 1 dB gain compression is +22 dBm typical and the output IP3 is +30 dBm typical. This amplifier is supplied in our standard PE2 housing that can be used with SMA connectors or as surface mount.

Science & Engineering Theme

Crossword for 11/25/2012

For the sake of avid cruciverbalists, each week I create a new crossword 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 Lamar).

Thanks to ISOTEC for

Long-Time Support

Since our inception in 1996 in Korea, ISOTEC has been a leading manufacturer of custom designed RF and Microwave Filters and sub-system products for wireless service providers. We provide recognized and trusted products and service to our customers in more than 30 countries worldwide. ISOTEC offers an extensive product mix with filters and Multiplexers that satisfy requirements from 100 kHz to 20 GHz. RF Connectors and cable assemblies are also present in our product portfolio.

ESD Basics: From

Semiconductor Mfg to Use

ESD Basics: From Semiconductor Manufacturing to Use, Steven H. Voldman (he was my Semiconductors class professor for two semesters at UVM) The text is unique in covering semiconductor chip manufacturing issues, ESD semiconductor chip design, and system problems confronted today as well as the future of ESD phenomena and nano-technology. Extensive coverage on the fundamentals of electrostatics, triboelectric charging, and how they relate to present day manufacturing environments of micro-electronics to nano-technology, semiconductor manufacturing handling and auditing processing to avoid ESD failures ESD, EOS, EMI, EMC, and latchup, component and system level testing to demonstrate product resilience from human body model (HBM), transmission line pulse (TLP), charged device model (CDM), human metal model (HMM), cable discharge events (CDE), to system level IEC 61000-4-2 tests, and ESD on-chip design and process manufacturing practices.

Happy Thanksgiving!

Happy Thanksgiving from RF Cafe!

Please Thank Dong Jin

Technology for Their Support

Dong Jin Technology Innovations designs, manufactures, and assembles RF connectors, cable assemblies, arresters, attenuators, adaptors, bias Tees, filters, terminations, directional couplers, power combiners, power dividers. Competitive price, on-time delivery and best quality. No minimum order size. One-day delivery.

Job Hunting Resources

IEEE Job Site Career Alert 11/22/2012 - RF CafeIEEE's Job Site Alerts are mailed out periodically with a handful or so of job hunting tips.

The 10 Non-California Tech Companies You Wish You Worked For (note: 37 Signals' Jason Fried writes a great monthly column in Inc magazine)

Are You Ready for the Phone Interview?

Burgeoning Microelectronics Sector Expects Jobs Growth

IEEE-USA Government Fellowships

IEEE-USA Government Fellowships - RF CafeLinking Science, Technology & Engineering Professionals with Government Each year, IEEE-USA sponsors government fellowships for three qualified IEEE members.  The fellows — chosen by the IEEE-USA Government Fellows Committee and confirmed by the Board — spend a year in Washington serving as advisers to the U.S. Congress and to key U.S. Department of State decision-makers. Known as either a Congressional Fellowship or an Engineering & Diplomacy Fellowship, this program links science, technology and engineering professionals with government, and provides a mechanism for IEEE's U.S. members to learn firsthand about the public policy process while imparting their knowledge and experience to policymakers.

The Secret to Eliminating ESD

Damage? Read Your Datasheet

The Secret to Eliminating ESD Damage? Read Your Datasheet - RF CafeESD is a big potential [pun intended] problem for modern electronics. Ultra small gate thicknesses and overall geometry miniaturization of ICs makes for vulnerability to shocks. All new IC designs incorporate some level of ESD protection, but discrete devices like transistors often do not. Low voltage electronics that operate off of just a couple volts are using super small capacitors and resistors that are only rated for 6.3 V. Improperly designed circuits can easily be taken out when you grab your cellphone or iPod on a cold, arid day. Design News' Charles Murray has sage advice for dodging such hazards: Read your datasheet. I would also suggest also researching the plethora of papers and books written on the subject.

FQXi: Is Reality Digital

or Analog?

Foundational Questions Institute: Is the World Analog or Digital? - RF CafeEach year the Foundational Questions Institute (FQXi) holds an essay contest inviting writers to submit missives addressing the question chosen by the FQXi board as being particularly thought-provoking. In their words, "FQXi catalyzes, supports, and disseminates research on questions at the foundations of physics and cosmology, particularly new frontiers and innovative ideas integral to a deep understanding of reality, but unlikely to be supported by conventional funding sources." The 2011 question was "Is Reality Digital or Analog?" Scientific American magazine, being one of three partners, published the runner-up entry in the December 2012 issue: University of Cambridge professor of theoretical physics professor David Tong's paper argues that the world is in fact fundamentally analog. Professor Tong actually tied for second place, but for some reason SciAm does not tell us whether the other second place paper supported an analog or digital viewpoint. For that matter, it did not say which side the winning paper came down on. Strange. I looked it up on the FQXi website. First place went to Jarmo Makela, who believes reality is digital in nature based on a personal discussion with Isaac Newton in his London home in the year 1700. When...

Hams on the Alaska Highway

Hams on the Alaska Highway, April 1945 QST - RF CafeEven though my fingers stop working when exposed to temperatures below freezing, I love the northern climate - four full seasons, snow, iced-over lakes, migrating birds, fiery autumns, cool summers, the whole experience. Having the option of not participating in the cold outdoor environs is what makes it good. However, the U.S. Army Signal Corps guys pulling duty in Alaska during World War II did not have that luxury. As told by radio engineer Major Colvin in this story from a 1945 edition of ARRL's QST magazine, winter life in Alaska at -40° was a real challenge. It was a world where Prestone antifreeze froze, the sun shone only a few hours a day, vehicles had to be left running 24/7 or risk not being able to be re-started, and mile-long treks between buildings was common. There were no snowmobiles. The success of the communications station was attributed to "the high percentage of amateur radio operators and technicians."

Pasternack Intros New Line

of HF PIN Diode RF Switches

Pasternack Enterprises Introduces New Line of High Frequency PIN Diode RF Switches - RF CafePasternack Enterprises introduces their new line of high frequency RF switches. These high isolation RF switches have frequency ranges from 500 MHz to 40 GHz and a power rating of 0.1 Watts (+20 dBm).

Please Welcome Advertiser

Venture Technologies!

Venture Technologies designs and develops innovative wireless products that measure, analyze and control. RFOS - a customizable, modular wireless platform - results in better products that cost less to develop. The cost and performance of full custom with the ease of a module. An in-house developed customizable, modular wireless platform, RFOS™, allows better, faster development with lower NRE costs. Core embedded wireless capability is wrapped in full service "spec to production" product development.

China to Build World's Tallest

Skyscraper in 90 Days!

China to Build World's Tallest Skyscraper in 90 Days! - RF CafeChina's about to do it again. The country that two millennia ago built the Great Wall has awoken from a long slumber to, beginning two decades ago, accomplish a long string of world-record-breaking projects. What used to be the domain of American and Western ingenuity is now the realm of Chinese engineers and craftsmen. Of course much of the capability originated in Western schools and corporations, but the Chinese people have proven to be quick learners and motivated, highly capable creators. While America is in the process of destroying personal freedoms and demonizing hard work, academic excellence, and capitalism, China is doing just the opposite. Our leaders are pathetic one-world weaklings while theirs are strong and nationalistic. The result is obvious to all with eyes open. China's latest feat will be to build the world's tallest skyscraper in just 90 days!. "Sky City One" (aka J220) as planned is 2,750 feet tall and will beat Dubai's Burj Khalifa by 33 feet at half the cost. Nearly 95% of the structure will use prefab sections to create 10.8e6 square feet of office space on 220 floors, all connected by 104 elevators. It will be complete by the end of this coming winter - compliments of WalMart shoppers.

Viel Dank to Reactel for

Continued Support


Reactel designs and manufactures RF and microwave filters, diplexers, and subassemblies, DC-50 GHz. Suspended substrate, LC, ceramic, tubular, miniature cavity, waveguide, switched filter banks, combline, interdigital. Contact them with your specifications.