Homepage - RF Cafe
Webmaster: Kirt Blattenberger | KB3UON | Sitemap | ©1996-2014
Menu below is just a small sample of what is here!
 
Custom Search
More than 10,000 searchable pages indexed.
•−•  ••−•    −•−•  •−  ••−•  •
RF Cafe Morse Code >Hear It<

Homepage Archive September 2013

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 Google Search box in the upper left corner of every page
Homepage Archive Pages
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13
2013:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

2014:  Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec

Here is page 2 of the September 2013 homepage archive.


Hittite's GaAs MMIC SP4T
Reflective Switch for 23-30 GHz

Hittite's New GaAs MMIC SP4T Reflective Switch Covers 23 to 30 GHz - RF CafeHittite Microwave, the world class supplier of complete MMIC based solutions for communication & military markets, has introduced a new reflective, SP4T switch that is ideal for demanding applications requiring broadband performance, low insertion loss, fast switching speed and high power handling capability. The HMC1084LC4 is a broadband reflective GaAs MESFET SP4T switch that provides frequency coverage from 23 to 30 GHz, with 11 dB return loss, 26 dB isolation and 2.8 dB insertion loss at 30 GHz, and a switching speed of 15 ns.

Radio & Radar Crossword
Puzzle for September 15th

Radio & Radar Crossword Puzzle for September 15, 2013 - RF CafeTake a much-deserved break and work this week's Radio & Radar themed crossword puzzle. This one won't take too long. All the words are pulled from a hand-built list of terms, names, and abbreviations that have only to do with science, mathematics, and engineering. If you want a crossword with names of movie stars and obscure countries, try the local newspaper. If you want to exercise your nerd knowledge, this is the one for you.

NuWaves Receives ISO 9001
and AS9100 Certifications

NuWaves Receives ISO 9001 and AS9100 Quality Management System Certifications - RF CafeNuWaves Engineering, an international Radio Frequency and Embedded Systems solutions provider, announces it has achieved both ISO 9001:2008 and AS9100:2009 Rev C certifications for its Quality Management System by EAGLE Registrations Inc. Its scope includes research and development as well as design and production of RF systems and subsystems. "NuWaves is excited to join the top tier suppliers in our industry with these highly respected quality certifications," said Jeff Wells, President and CEO of NuWaves Engineering. "It's a testament to our employees and their dedication."

PMI Intros Integrated Front-End
Unit for Phased Array Radar

PMI Intros Integrated Front-End Unit for Phased Array Radar - RF CafePlanar Monolithics Industries has introduced PMI Model No. IFE-DRS-KIT, an Integrated Front End (IFE) unit that consists of a low noise amplifier, RF Log Detector, and a low noise video amplifier. This integrated unit was designed to support a phased array radar automated test set. Operational frequency is in the 9-10 GHz band with an input power level of -40 to -48 dBm.

White Paper - Considerations
for Wireless Range

White Paper: Considerations for Wireless Range - RF CafeLinx Technologies has published a white paper titled, "Considerations for Wireless Range." Author Justin Hopper writes, "One of the first questions one asks when evaluating a wireless system is 'what range will it get?' The answer to the wireless range question is somewhat complicated. The range of a wireless system is dependent on several interdependent factors. Some are internal to the design of the product and some are external. There are ways of estimating the wireless range of a system by taking into account several factors. The first factors in determining wireless range..."

ESD Between
Engineers and Technicians

Static Between Engineers and Technicians - RF CafeMy electronics career began in the USAF as a radar system maintenance specialist, where I did not have exposure to engineers except a rare visit by a communications officer during system certification tests. Following separation (aka "getting out"), I went to work as an electronics technician for Westinghouse at the Oceanic Division in Annapolis, Maryland. It was the first time I worked alongside engineers. My nature is to be subservient and respectful toward people put in charge of my activities, whether at work or otherwise, so I was surprised to witness an underlying rift that persisted between engineers and technicians. A minority of the techs seemed to harbor resentment for the engineers and took every opportunity to highlight their mistakes, no matter how minor. Derisive comments were usually reserved for the benefit of co-workers, not the engineers themselves (backbiting). I admired most of the engineers enough that it motivated me to spend many years taking classes part-time to earn my own BSEE degree. On one occasion a production test technician discovered an incorrect voltage reference level on a comparator circuit in a very complex mixed signal circuit...

11th Annual Military Antennas

11th Annual Military Antennas - RF CafeIDGA's Military Antennas East Summit will address the evolving development of antennas as an ever-critical component of all military communication capabilities; in doing so, it will delve into the development of Ground, Air, Sea, and Space-based antennas, along with software radios, vehicle communications, and SATCOM. It will also uncover the newest in antenna technology, including small wideband antennas, metamaterial antennas, GPS programs, superconducting RF systems, adaptable RF, and more. Washington Plaza Hotel, September 17-18, 2013.

UP! - The Real Thing

UP! - The Real Thing as Jonathan Trappe Attempts Atlantic Crossing - RF CafeAs you read this, veteran North Carolina balloonist Jonathan Trappe is floating over the Atlantic Ocean somewhere right now in a small wicker gondola lifted aloft by a cluster of colorful party balloons. It departed from Maine on Thursday, September 12, 2013. A story on the ARRL website reports that amateur radio is onboard. Mr. Trappe is no newcomer to flying in such contraptions. In 2012 he and a specially designed small house used a similar buoyancy arrangement to float above Mexico. A "toy balloon" flight over the Alps met with success in September of 2011. Trappe became the only person to have crossed the English Channel by cluster balloon...

When an Expert's Testimony
Counters His Own Report

Bob Ambrogi, IMS ExpertServicesIMS ExpertServices periodically sends out e-mails that highlight recent key court cases that can significantly affect the effectiveness of expert testimony, both for the plaintiff and for the defendant. When an Expert's Testimony Counters His Own Report, by IMS Expert Services - RF CafeThis latest case involves an expert who contradicted during oral testimony what he claimed in his written report. The mistake cost the company that hired him as an advocate to lose their patent infringement claim. I'm guessing the company has initiated a new lawsuit based on the outcome. Attorney Robert Ambrogi weighs in on the situation...

Channel Master Antennas
Advertisement

Channel Master Antennas Advertisement - RF CafeOne sure giveaway to the age of a picture is the presence of a wheat penny, a buffalo nickel, or a Mercury dime. This 1957 advertisement for Channel Master antennas has all three. It shows a walking Liberty half dollar as well. Quarters haven't changed much over the years, with George Washington's head on the obverse side since 1932. The wheat penny design ended in 1959 when the Lincoln Memorial was put on the reverse side in its place. Thomas Jefferson's head has been on the nickel since 1938. Theodore Roosevelt's head was ensconced on the obverse of the dime in 1946. John F. Kennedy was placed on the half dollar obverse in 1964. This ad is about antennas, not coins, though. For a lot, if not most, of RF Cafe visitors, there has always been cable and satellite television. For some, TV has always been...

Please Welcome Nortec RF
As My Newest Advertiser

Nortec RF ComponentsNortec RF is an engineering design and manufacturing company specialized in RF and Microwave products, with more than 22 years of experience designing power combiners and dividers, directional couplers, hybrid couplers, and filters. Their research and development group and engineering team constantly introduces new, top of the line products into the product line. Please visit Nortec RF today and thank them for helping to deliver RF Cafe.

'Tornado' Banned by U.S.
Weather Bureau Before Radar

'Tornado' Banned by U.S. Weather Bureau Before Radar - RF CafeDid you know that from 1885 until 1938, prior to the advent of radar, the U.S. Weather Bureau banned the use of the word 'tornado' in weather forecasts? According to a story in Spectrum magazine, the bureau thought the mere mention of the word would strike fear in people and prevent them from settling in tornado-prone Midwest and western plains regions. Believe it or not, the decision was made in part because local business owners complained that customers stayed home in shelters rather than shopping at their establishments when a tornado warning was in effect. An early tornado warning system was devised that was so hokey that it is no surprise it never worked well enough to be adopted. A single wire with a series current running through it was strung between all the houses and along a stretch of land southwest of town (most probable approach direction of tornados). The current energized a solenoid that held cocked the hammer of a bell. If a tornado broke the wire anywhere, the bells in all outfitted homes would strike to warn occupants of immediate danger. I suppose it was better than nothing, but not very practical or effective, especially if a stray cow or mischievous kid broke...

Dongjin TI Intros N-Type
Calibration Kit

Dongjin Technology Innovation Intros N-Type Calibration Kit - RF CafeDongjin Technology Innovation announces the immediate availability of an N-Type Calibration Kit for use with high precision network analyzers and other test equipment requiring calibrated short, open, or 50 Ω load. A patented design delivers 10% higher electric performance at 50% low cost and very fast delivery. Contact Dongjin Technology Innovations today for details and pricing.

Thanks to Triad RF Systems
and DCH Systems for Support

Triad RF Systems + DCH Systems Merger : RF Cafe
In case you haven't heard, Triad RF Systems and DCH Systems have combined forces recently to bring you a powerhouse of amplifier design expertise. Dean Handrinos and Steve Barthelmes are highly capable RF amplifier and system designers who each leveraged expertise gained from prior industry experience to start their own companies a few years ago. I didn't ask how Triad RF Systems was chosen as the new name for their merged companies - maybe it was a coin toss. Very soon you will see the DCH Systems ads disappear from RF Cafe, but you can still reach Dean at Triad RF Systems. If you have a chance, please contact them and wish them good fortune on their new endeavor.

American Astronauts Back
from ISS... Courtesy of Russia

American Manned Space Program Embarassment - RF CafeExpedition 36 crew members Chris Cassidy of NASA and Pavel Vinogradov and Alexander Misurkin of the Russian Federal Space Agency have returned to Earth from the International Space Station, landing safely in Kazakhstan at 10:58 p.m. EDT Tuesday. Cassidy, Vinogradov and Misurkin, who launched to the station March 29, spent 166 days in space. They completed 2,656 orbits of Earth and traveled more than 70 million miles. Vinogradov conducted one spacewalk, bringing his career total to seven spacewalks with an accumulated time of 38 hours, 25 minutes. Misurkin conducted three spacewalks...

NXP Makes UHF PCB Antenna
Design as Easy as 1, 2, 3

Transim RFID Antenna PCB Pattern - RF CafeElectronic equipment manufacturers Transim RFID PCB Antenna Radiation Pattern - RF Cafewanting to embed RFID technology in their products are now able to do so without needing deep UHF antenna design experience thanks to NXP Semiconductors' new online software tool. The RFID – PCB Antenna Designer tool helps implement antennas on a PCB in the UHF frequency range (840-960 MHz). UHF antenna design is more complex than a typical HF antenna design and needs an expert understanding of the electronic design constraints. With the RFID – PCB Antenna Designers can simply input parameters, such as space available on the PCB, target performance, board materials, and target frequency range in the region of application to receive a turnkey UHF antenna design for their specific application.

So This Is What Darkness
Looks Like

So This Is What Darkness Looks Like - RF CafeAn Al Qaeda attack on the power grid was my first thought on this eve of the 9-11 anniversary. When we arrived at Erie's World of Music at 7:00 PM for Melanie to take her music lesson, we were greeted by employees telling us all lessons were cancelled due to a power outage. The lights were on when we left home 15 minutes earlier, and were still on when we got back. Isn't it odd how a music school can't function these days without power because most of the instruments use electricity? The acoustic guitars have electronic pick-ups now just like classic electric guitars, pianos are synthesized keyboards, and even the drum sets are electronic look-alikes. Having it that way facilitates keeping noise levels down during the dozen or more instruction sessions happening at any given time. It can get pretty loud in the WoM basement even with volumes turned down...

Z-Comm Intros Fixed Freq.
Synth with Ultra Low Φ Noise

Z-Comm Intros Fixed Frequency Synthesizer with Ultra Low Phase Noise - RF CafeZ-Communications, Inc. announces a new RoHS compliant Fixed Frequency Synthesizer model SFS10000C-LF in X-band. The SFS10000C-LF is a single frequency synthesizer that operates at 10 GHz and features a typical phase noise of -100 dBc/Hz @ 10 KHz offset and typical sideband spurs of -70 dBc over the temperature range of -40º to 85º C.. The SFS10000C-LF is designed to deliver a typical output power of 0 dBm with a VCO voltage supply of 5 Vdc Typical 2nd harmonic suppression of -30 dBc. SFS10000C-LF is an excellent choice for broadband transmission and fixed wireless applications.

September 11, 2001
3,000 Souls Lost
Untold Freedoms Lost

September 11, 2001 Remembered - RF CafeTwelve years ago on this date Americans had their worlds turned upside-down with the news of hijacked airliners crashing into the two World Trade Center towers, the Pentagon, and a field in Shanksville, Pennsylvania. For a myriad of reasons ranging from political correctness to incompetence, the many indicators of such an attack being perpetrated were ignored. Then, as now, news agencies and government offices refuse to identify the terrorists as extremist Muslims. As you remember that horrific day, keep in mind all of the American and ally servicemen who have died or have been gravely wounded in following years, and think of the multitude of freedoms you have lost since then...

Hittite Intros2 W GaAs pHEMT
MMIC PA Covers 15 to 20 GHz

Hittite Intros 2 W GaAs pHEMT MMIC Power Amplifier Covers 15 to 20 GHz - RF CafeHittite Microwave has launched a new power amplifier which maintains excellent performance over its operating frequency range. The HMC6981LS6 is ideal for high linearity point-to-point and point-to-multi-point radios, SATCOM, military and space applications. The HMC6981LS6 is a four-stage GaAs pHEMT MMIC power amplifier which operates between 15 to 20 GHz. Ideal for covering the 18 GHz licensed microwave radio band, the amplifier provides 26 dB of gain, +34.5 dBm of saturated output power, and 25% PAE from a +6 V supply. Up to +43.5 dBm OIP3 and drawing only 1100 mA  from a +6 V supply.

Modern Radio Practice
in Using Graphs and Charts

Modern Radio Practice in Using Graphs and Charts, July 1932 Radio News - RF CafeI've always had a problem with book and article titles containing the word 'Modern' because it is utterly ambiguous. What was modern in 1932 is usually obsolete merely a decade later, especially in high technology (not so much in buggy whip state-of-the-art methods, though). Sometimes, as with this article on insulation breakdown voltages, bringing the information up to date requires only the substitution of a few words. For instance, replace 'condenser' with 'capacitor' and units of 'mfd' with 'μF' and 'mmfd' with 'pF,' then you'll be on your way to gaining useful information. There is a nice nomograph for use in designing capacitors for specific voltage handling and a table of dielectric puncturing voltages as well.

Dongjin TI Intros Composite
DIN 7/16 Connector

Dongjin Technology Innovation Intros Composite DIN 7/16 Connector - RF CafeDongjin Technology Innovation announces the immediate availability of very affordable, patented, composite DIN 7/16 connectors. The body material is a composite plastic black with silver-plated bronze contacts, as opposed to a standard brass body and beryllium-copper (Be-Cu) contacts. This newly developed 7/16 connector is seeing a steep increase in use in leading countries like Japan, Germany, and the USA.

RF Cafe Featured Book

Basic Antennas: Understanding Practical Antennas and Design - RF Cafe Featured BookBasic Antennas: Understanding Practical Antennas and Design, by Joel R. Hallas (QST's "The Doctor Is In" columnist). Basic Antennas is a comprehensive introduction to antennas--basic concepts, practical designs, and details of easy-to-build antennas. You'll learn how to make antennas that really work! This book will provide a foundation in antenna theory and design necessary for anyone undertaking more advanced topics such as those presented in The ARRL Antenna Book. Includes: Dipole Antennas, Antenna Impedance, Transmission Lines, Practical Two Element Arrays, Wideband and Multiband Antennas Reflector Antennas, Yagis for HF and VHF, Loop Antennas, Antennas for Microwave Applications, Vehicle Antennas, Antenna Measurements, Plus, an Introduction to Antenna Modeling...and much more!

Modern Vacuum Tubes

Modern Vacuum Tubes - RF CafeIt is no secret that I have a soft spot in my heart for vintage electronic equipment, particularly vacuum tube radios. Believe it or not, you can even today buy a new radio with tubes, but the tubes will only be in the speaker driver circuit. The front-end tuner circuitry will be solid state. That's OK, because you still get a "real" orange glow from the tubes. If you really want a nostalgic experience, you will need to procure an authentic vintage radio. Until about a decade ago, you used to be able to jokingly say that you have a computer or a television that still uses vacuum tube technology. Now that there are virtually no CRT computer monitors or TV screens in service (in 1st-world countries, anyway), you can't get away with it. Bummer. I suppose someday when holographic or direct neural imaging is commonplace, late-adopter types (like me) will joke about our computers and TVs still having physical displays. On of the few remaining realms for vacuum tubes is high power transmitters used in radio and television broadcasting. It is evidently still cheaper and easier to build a tube... 

JFW Intros Two Mini-Benchtop
Programmable Attenuators

JFW Industries Intros Two Mini-Benchtop Programmable Attenuators - RF CafeJFW Industries, Inc. is pleased to announce two new additions to our series of mini-benchtop, programmable attenuator assemblies.  The 50BA-011-95 offers 0-95 dB of attenuation in 1 dB steps from 200-6000 MHz, while the 50BA-010-127 gives 0-127 dB and operates 700-3000 MHz. Other configurations are also available. The mini benchtop models are JFW’s latest line of attenuator assemblies. These units are DC powered using a wall transformer that is shipped with each unit. The attenuation of each variable attenuator is displayed on the front panel. Controlled remotely or manually.

Many Thanks to Dow-Key
for Continued Support

Dow Key MicrowaveDow-Key Microwave Corporation is the world's largest manufacturer of electro-mechanical RF switches. They are AS9100/ISO-9001 certified and committed to providing unparalleled customer service, competitive pricing, on-time delivery and switch products that are distinguished by quality and reliability. Dow-Key offers the largest switch product line in the world with over 10,000 unique configurations.

Student's Radio Physics
Course - Series & Parallel

Student's Radio Physics Course, July 1932 Radio News - RF CafeNot everyone who visits websites like RF Cafe are seasoned electronics veterans. While you and I can do series and parallel circuit analysis (and series/parallel for that matter, possibly using Fourier or La Place transforms for reactive AC circuits) in our sleep, many are recently getting into the wonderful world of electronics who are just coming of age or have suddenly at a later point in life developed a passion for the craft. Accordingly, this article from Radio News provides yet another tutorial on the fundamentals of series and parallel circuit analysis. Only resistors and basic Ohms law are covered.

Please Welcome LadyBug
As My Newest Advertiser!

LadyBug TechnologiesFounded in 2005, LadyBug Technologies manufactures the PowerSensor™ line of miniaturized USB RF & microwave power sensors. LadyBug manufactures high accuracy average, pulse, and pulse profiling sensors with GUI interfaces covering up to 26.5 GHz and 80 dB dynamic range. These sensors set a, patented industry standard, No Zero / No Cal technology. There is no need to disconnect or wait for internal zeroing and calibration prior to making accurate low power measurements. Driver support is provided.

Please Visit Cobham Antennas
In Appreciation of Support

Cobham Antenna SystemsCobham Antenna Systems, formerly European Antennas, has been a long-time advertiser on RF Cafe. Cobham specializes in the design and development of high gain, printed circuit antenna arrays, ultra wide-band directional antennas, multi-octave bicones and high gain collinear omni-directional antennas. They have a large catalogue of antenna designs. Specialist development projects from 250 MHz to 40 GHz. Communication industry awareness and expertise in antenna physics ensure customer satisfaction is their forte.

Notable Tech Quote

"If you've got someone who's good in an emergency, get rid of him or you'll always have emergencies." - RF Cafe Notable Quote"If you've got someone who's good in an emergency, get rid of him or you'll always have emergencies." Anon - old engineering saying per Sherlock Ohms author Rod Hine.

Microwave Engineering
Crossword for 9/8/2013

Microwave Engineering Crossword Puzzle for September 8, 2013 - RF CafeTake a much-deserved break and work this week's Microwave Engineering themed crossword puzzle. All the words are pulled from a hand-built list of terms, names, and abbreviations that have only to do with science, mathematics, and engineering. If you want a crossword with names of movie stars and obscure countries, try the local newspaper. If you want to exercise your nerd knowledge, this is the one for you.

Simplifying Signal Analysis
in Modern Radar Tests

Simplifying Signal Analysis in Modern Radar Tests - RF CafeThanks to Rohde & Schwarz, a leading manufacturer of RF & microwave test equipment, for allowing this reprint for their "Simplifying Signal Analysis in Modern Radar Tests" article that appeared in Microwave Journal's August 2013 edition of Military Microwaves publication. The R&S FSW-K6 Signal and Spectrum Analyzer is used to make measurements and for screen shots.  "The evaluation of direct digital synthesis (DDS)-based radar systems is challenging for traditional signal analysis test techniques. This is especially true when it comes to pulse compression analysis, pulse trend analysis over time and frequency agility verification. The test tools used to simplify the testing of modern radar systems are evolving, like the systems they must test. This article focuses on the evolution of spectrum analyzers from relatively basic instruments used for measuring traditional pulsed signals to the advanced test system architectures required for signal analysis of leading-edge radars. Sophisticated, next-generation radar systems benefit from advances in digital technology and computational power. The trend is toward the use of DDS to enable powerful wideband waveform..."

Advanced Test Equipment
Rentals - Thanks!

Advanced Test Equipment Rentals - RF CafeThanks once again to Advanced Test Equipment Rentals for supporting RF Cafe through continued advertising. Please consider their services when looking for test equipment. ATER (aka ATEC) provides the latest models of test and measurement equipment from top name manufacturers like Agilent, Fluke, Anritsu, R&S, Tektronix, and Yokogawa. Their primary focus is providing a complete rental solution of test and measurement equipment to industries such as Aerospace, Defense, EMC, and Communications.

500 W HPA in 3U Chassis Only
from Empower RF Systems!

500W HPA in 3U Chassis Available Only from Empower RF Systems! - RF CafeEmpower RF Systems continues to leverage next generation hardware and software architecture and is proud to introduce the next series of the "size matters" portfolio - 500 W in 3U chassis. This new PA family operates in the frequency ranges of 20 - 500 MHz (Model 2173), 500 - 1000 MHz (Model 2174) and 20 - 1000 MHz (Model 2175) with the output power guaranteed over full bandwidth and temperature. You won’t find another HPA alternative in the marketplace that rivals our unique combination of package, size, weight and power, not to mention, an inventory program from a global distributor Richardson RFPD.

Explain Radio Fading
to the Public

Explain Radio Fading to the Public, September 1942 Radio Retailing Today - RF CafeThis is a great primer for anyone looking for an easily understandable way to explain the basics of radio signal fading to acquaintances, or for that matter to understand it yourself if you don't already. As I review the material for taking my amateur radio General Class exam, there is information about atmospheric absorption in the various ionospheric layers during daytime and nighttime. Prior to studying the manual, I either never knew or once knew but have forgotten about the upper F1 and F2 layers combining into a single layer at night when the sun's radiation and particle bombardment is blocked by the earth. This article doesn't go that deep into the physics, but it does a good job of making a complex topic simple enough...

Nokia (Microsoft)
Cellphone Evolution

Nokia (Microsoft) Cellphone Evolution - RF CafeNokia has been in the news lately for having sold its cellphone line to Microsoft for $7.2 billion (US). Was it a good move? At least immediately, it depends on whether you owned Microsoft stock or Nokia stock. Responding to the news, Microsoft's stock shed $1.52 (-4.6%) to close Tuesday at $31.88. Nokia's shares surged $1.22 (+31%), to finish at $5.12. Microsoft's Windows Phone operating system has been in Nokia phones since 2011. Nokia was knocked from its #1 rank pedestal a couple years ago and is currently in the #2 slot, with Apple following, then China's ZTE. Nokia's debut in the cellphone realm was in 1992 with the Mobira Senator. It wasn't quite a bag phone, but...

Thanks to Res-Net Microwave
for Continued Support!

Res-Net MicrowaveFor over 25 years Res-Net Microwave has manufactured precision RF & microwave attenuators, terminations, and other components, and now diode detectors for commercial, military, and space applications. Res-Net Microwave is a leader in the development and production of the metal films required for these types of RF/microwave attenuators, terminations, and resistors up to 2 kW. Now offering 4-week lead times on standard products including: attenuators, resistors, and terminations.

A Question About
Transmission Line Impedance

Sample Smith Charts for S-parameters - RF CafeNote: See answer submitted by Greg F.
RF Cafe visitor L. Joseph wrote to request that the following question be posted in hope that someone will provide an answer. If you care to reply, please either e-mail your answer to me so I can post it, or reply on LinkedIn.
"This is the question I am trying to get an answer for: Let us take a 100 ohm termination in a 50 ohm system and add a 50 ohm transmission line of 0.2 lambda (0.2λ) length. At the end of this 0.2 lambda line I will get an impedance corresponding to some VSWR1. Then, I change the termination from 100 ohms to 75 ohms and at the end of the 0.2 lambda line VSWR2 will be VSWR2 = VSWR1/(100/75) = VSWR1/1.33. Will the same rule apply..."

Kete Microwave Intros
Two New Step Attenuators

Kete Microwave Intros Two New Step Attenuators - RF CafeKete Microwave Intros Two New Step Attenuators (Single) - RF CafeKete Microwave Company announces two new additions to their line of RF variable/step attenuators. Both models are panel mountable and have SMA connectors. Part number DRA2-2.7-30-SMAF (left) is a Dual Rotary Attenuator with an attenuation range of 0-30 dB from DC-2.7 GHz with a VSWR of 1.30:1 to 1.40:1. Part number SRA2-2.2-10-SMAF (right) is a Single Rotary Attenuator with an attenuation range of 0-10 dB from DC-2.2 GHz . Both units handle up to 2 W at an operating temperature range from -55°C to +85°C.

Measurements with
Scattering Parameters

Measurements with Scattering Parameters - RF Cafe

RF engineer Joe Cahak, owner of Sunshine Design Engineering Services, has written a series of white papers on S-parameters. This third installment is titled, "Measurements with Scattering Parameters." "In many RF and Microwave measurements the S-Parameters are typically expressed in dB (decibels) Magnitude units and Degrees in the polar coordinate system. Network and Vector Network Analyzers and Spectrum Analyzers all measure with voltage ratio measurements, so to convert to dB in terms of volts we must use the following equation..."

Not All Common Currents
Are Bad

Not All Common Currents Are Bad - RF CafeHere is an interesting short article on the EDN website. Author Eric Bogatin, who has written books such as Signal and Power Integrity - Simplified, asserts that common [mode] currents (he detests the 'mode' term), while not desirable, are not always a matter of concern. "Generally, if the return path of the common current is far from the signal path, then these common currents will radiate. These are bad common currents. But if you can engineer the return path of the common current to be in proximity to the source current, the loop area will be small and he common current will not radiate." "Not all common currents are bad. Give microstrip traces a break."

KindCards
e-Cards with a Mission

KindCards - e-Cards with a Mission - RF CafeMike Press was a department manager at RFMD during my 6½ years there as an RF Applications Engineer. While he and I only worked together a couple times, we did manage to hold a few memorable discussions - usually on holidays when most normal people had taken the day off - on a broad range of social, economic, and national defense topics. None of humanity's problems were ever solved as a result of our dialogs, but I did come to have a great respect for Mike's worldview as what I deem a classical Liberal. By that I mean one whose focus is on compassion for his fellow man and truly wanting to foster unity, as opposed to many modern Liberals who seem angrily intolerant and want to destroy anyone that disagrees with any of their positions. Yes, some Conservatives are regrettably that way as well...

Congrats to August Book
Drawing Winner Steve L. !

August 2013 Book Drawing Winner: High-Frequency Integrated Circuits (Quiz #49:) - RF CafeEach month I select someone to receive a free book from those provided by Artech House and Cambridge University Press. They are often books I have used to create quizzes. How to enter? Either buy one of my inexpensive software offerings or send me an e-mail. This month's winner, Steve L., selected Introduction to High-Frequency Integrated Circuits (Cambridge University Press), by Rosin Voinigescu. "A transistor-level, design-intensive overview of high speed and high frequency monolithic integrated circuits for wireless and broadband systems from 2-200 GHz, this comprehensive text covers high-speed, RF, mm-wave, and optical fibre circuits using nanoscale CMOS, SiGe BiCMOS, and III-V technologies..."

Skyworks Intros FEM for WiFi
in Handsets and Tablets

Skyworks Introduces WiFi Connectivity Front-end Module for Handsets and Tablets - RF CafeSkyworks Solutions unveils a highly integrated, 5 GHz front-end module for wireless connectivity, Bluetooth and mobile applications that exceeds 802.11n system requirements.  The SKY65535-11 integrates a power amplifier, a low noise amplifier with bypass, and a single-pole-double-throw, transmit/receive switch in a 16-pin, 2.5 x 2.5 mm, quad-flat-no-lead package.  Because the solution provides a direct connection to the battery with a 3.6 V nominal supply voltage that removes the need for regulators and associated components, the module reduces the overall bill of material costs and space requirements on the circuit board. An integrated power detector with 20 dB of dynamic range that delivers closed-loop power control within the system.

Featured Book of the Week
Microwave Mixer Technology

Microwave Mixer Technology - RF Cafe Featured BookMicrowave Mixer Technology, by Bert Henderson and Edmar Camargo, is published by Cambridge University Press. Although microwave mixers play a critical role in wireless communication and other microwave applications employing frequency conversion circuits, engineers find that most books on this subject emphasize theoretical aspects, rather than practical applications. That's about to change with the forthcoming release of Microwave Mixer Technology and Applications. Based on a review of over one thousand patents on mixers and frequency conversion, authors Bert Henderson and Edmar Camargo have written a comprehensive book for mixer designers who want solid ideas for solving their own design challenges.

Dongjin TI Intros High
Performance Connectors

Dongjin Technology Innovation Intros High Performance Connectors - RF CafeDongjin Technology Innovation announces the immediate availability of very high performance connectors. Industry standard connector types have useful frequencies extended from the typical 11 GHz up to 18 GHz using proprietary constructions such as soldered shield connections for better isolation and higher pull-off force. Contact Donjin Technology Innovations today for details and pricing.

Please Visit Windfreak in
Appreciation of Their Support

Windfreak Technologies Windfreak Technology designs, manufactures, tests and sells high value radio frequency products such as RF Signal Generators, RF Synthesizers, RF Power Detectors, RF Mixers, RF Upconverters and RF downconverters. They develop high quality, reliable, low cost products to make your life easier. Windfreak Tech is developing high quality, low cost products to make life easier for RF Engineers and hobbyist. Future products will be more synthesizers, transmitters, receivers and test equipment. All at low cost.

Notable Quote

Notable Quote: "A fool with a tool is still a fool" - RF Cafe"A fool with a tool is still a fool." - Anon. This comment was left by a website visitor in response to the news story about a drone operator who ran his craft into a groom's head while filming a wedding video.

Fundamentals of Color TV
Tri-Gun Receiver Circuits

Fundamentals of Color TV, Tri-Gun Receiver Circuits, June 1954 Radio & Television News - RF CafeThis was a multi-part series published by Radio & Television News in the days when color TV was the domain of the more well-to-do folks on the block. Needless to say, nobody I knew had color TV before abound 1968. One of my friend's father owned a fairly profitable gas station and service garage, so they were the first to have one. For some inexplicable reason, his mother never allowed more than one or two of us into the house at a time, so we drew straws to see who got to witness that fabled miracle of technology. I was about third in line. Insomuch as the 1960s were a much more polite and private time than the present, peeking through a living room window for a preview was expressly verboten. In fact, going into a friend's house for any reason was rare. The privileged appointments were strictly adhered to...

Free White Papers

Free White Papers from RevResponse - RF CafeThe folks at Rev Response have a pretty big collection of white papers on a very wide range of subjects that are free for downloading. Well, not quite free - they do require you to sign in, but no $$$ is involved. I make a few pennies on each download, so you're helping to support RF Cafe if you participate. Here are a few of the newer ones that might interest you:

Cut That Cord! How to
   Ditch Cable
Windows 8 Keyboard
   Shortcuts Cheat Sheet
Aerospace Industry Takes
   a Fresh Look at Its Wire
   Harness Design Approach
Critical Success Factors for
   Consumer Electronics &
   Appliance Companies to
   Meet Today's Top 3 Issues
Top 5 Tips for Choosing
   Mobile Computers
7 Steps for Using Twitter
   for Small Business
Photoshop CS6 Unlocked:
   101 Tips, & Tricks -Free 61
   Page Preview

RF Engineering Crossword
for September 1, 2013

RF Engineering Crossword Puzzle for September 1, 2013 - RF CafeTake a break and work this week's RF Engineering themed crossword puzzle. All the words are pulled from a hand-built list of terms, names, and abbreviations that have only to do with science, mathematics, and engineering. If you want a crossword with names of movie stars and obscure countries, try the local newspaper. If you want to exercise your nerd knowledge, this is the one for you.

A Disruptive Web Presence

Custom Search
Over 10,000 pages indexed! (none duped or pirated)

Read About RF Cafe
Webmaster: Kirt Blattenberger
    KB3UON

RF Cafe Software

RF Cascade Workbook
RF Cascade Workbook is a very extensive system cascaded component Excel workbook that includes the standard Gain, NF, IP2, IP3, Psat calculations, input & output VSWR, noise BW, min/max tolerance, DC power cauculations, graphing of all RF parameters, and has a graphical block diagram tool. An extensive User's Guide is also included. - Only $35.
RF system analysis including
frequency conversion & filters

RF & EE Symbols Word
RF Stencils for Visio

Product & Service Directory
Personally Selected Manufacturers
RF Cafe T-Shirts & Mugs

RF Cafe Software

Calculator Workbook
RF Workbench
Smith Chart™ for Visio
Smith Chart™ for Excel
Your RF Cafe Progenitor & Webmaster
Click here to read about RF CafeKirt Blattenberger... single-handedly redefining what an
                                 engineering website should be.

View the YouTube RF Cafe Intro Video Carpe Diem! (Seize the Day!)

5CCG (5th MOB): My USAF radar shop

Airplanes and Rockets: My personal hobby website

Equine Kingdom: My daughter Sally's horse riding website