By 1970, the airwaves were really getting crowded. Lots of high power commercial and military gear was online, and the radio listening public was setting new record highs every year. As such, many new sources for radio interference were being discovered, and sometimes the problems caused went well beyond just a little noise being superimposed on top of Neil Diamond's newly released Cracklin' Rosie or the lads from Liverpool's The Long and Winding Road. Often, the interference was overwhelmingly annoying. The FCC was being flooded with complaints. Digital computers were creating a whole new...
This quiz is based on the new book Frequency-Agile Antennas for Wireless Communications , by Aldo Petosa. Proliferation of smart phones, tablets, and other portable devices are placing greater demands for services. Many of the proposed solutions to deal with these demands will have a significant impact on antenna designs. Antennas with frequency agility are considered a promising technology to help implement these new solutions. This book provides readers with a sense of the capabilities of frequency agile antennas, the widely diverse methods for achieving tunability, the current achievable performance, and the challenges still facing FAA designs.
The term "super-radar" would be sort of meaningless these days since just about everything is "super" anymore, especially with regard to military, space, or aerospace systems. Lately, when I hear the term "super-something," I think of a really funny radio commercial with a meeting of super-geniuses. I don't recall the exact subjects, but the chairman asks his members for items to add to their agenda of things to do. Someone pipes up with an idea to solve world hunger, then another suggests they design a nuclear fusion generator to power the world with clean energy, etc. Enthusiasm exudes from the empaneled super geniuses. Finally, someone suggests that they do whatever it is the commercial is trying to sell...
Fairview Microwave a preeminent supplier of on-demand microwave and RF components, has released a new line of compact hot-switchable variable attenuators. RF attenuators are used to reduce the amplitude of an electronic signature in many common electronic scenarios including lab testing equipment, distributed antenna systems (DAS) and power and signal monitoring systems. Fairview Microwave's new line of variable step attenuators come in 3 and 6 GHz frequency models and several different connector configurations including
This is really clever. Appearing in a 1955 edition of Popular Electronics, "The Electronic Husband" is one wife's attempt to quantify her husband's interest in all things electronic by adapting forms of Ohm's Law to fit observed behavior. In the process of writing the parody, Mrs. Jeanne DeGood demonstrates a good basic knowledge of Mr. DeGood's second passion. I think after all the articles that Melanie has proof read for me that she probably knows a lot of these equations as well.
AWR Corporation announces a new university portal added onto its main navigation menu that provides focused, in depth content to the company’s rapidly-growing academic user base. The site is clearly and concisely organized with dedicated areas for students, faculty, and graduates to easily navigate and get the information they need. The student portal offers links to educational content, tutorials and how-to, technical content, and information about other AWR University-focused content. The graduate portal provides ongoing educational
Planar Monolithics Industries has introduced Model Number PS-5G18G-400-A-SFF, a 5 to 18 GHz, low phase noise, analog phase shifter with capability for phase shifting from 0 to 400°. Operates from a single positive control voltage of 0 to +10 VDC with a phase voltage sensitivity of 40°/volt. This model offers a typical modulation bandwidth of 50 MHz and is supplied in our PE2 housing measuring only 1.08” x 0.71” x 0.29” and can be used with the SMA connectors or in a surface mount configuration. A new test report has been added to our web site wish contains phase noise data.
RCA's Numitron was their answer to the Nixie tube (manufactured by Burroughs Corporation). It was a simpler 7-segment incandescent display that, with all lines energized, formed the number 8. It worked off +3.5 to +5 volts, with each element requiring 24 mA of current. The number 8 drew 192 mA of current and dissipated 0.672 W at 3.5 volts and a whopping 0.96 W at 5 volts! RCA marketed a BCD-to-7-segment display driver. The Numitron was pitched as a sensible alternative to the 7-segment LED display, but with an element size of 0.35" wide by 0.6" high, there was no real advantage over the LEDs, which were just...
NuWaves Engineering is a veteran-owned premier supplier of RF systems, subsystems, RF products and Engineering Design Services designed to customer requirements. We are a turnkey provider for RF and Microwave communication custom designs with full project management and design responsibilities; taking ownership from the conceptual idea to production. Learn about NuWaves' capabilities.
Here is a little electronics hobbyist humor in the form of a comic series titled "Hobnobbing with Harbaugh," compliments of Popular Electronics. Citizens Band radio and dirty hippies were the topic of the day in the 1970, so that's what you see in a couple of these comics. The marriage proposal comic can be considered as 'amateur' in more ways than one! You don't need to be an amateur radio operator to appreciate these comic strips.
Sure, these articles are used to pitch company products, but they also offer useful information on application and state of the art components and systems. Companies like Hittite have a huge inventory of RF components that cover a wide array of technologies. Lots of radar-related stuff this time...
Skyworks Solutions an innovator of high performance analog semiconductors enabling a broad range of end markets, today announced that is has captured hi-rel and COTS sockets with several aerospace and defense suppliers such as Cobham, EADS, Herley and Teledyne. Skyworks’ solutions are being leveraged for microwave switching, attenuation, receiver protection and mixer and detector applications in commercial and military radios, avionics systems, software defined radios and navigation platforms that support major tier-one aerospace and defense companies such as Boeing, L-3 Communications, Northrup Grumman and Raytheon.
As legend goes, the use of microwaves for preparing food was pursued after a serendipitous discovery by Raytheon engineer Percy Spencer whereby he noticed the chocolate bar in his pocket had melted while he was working near a radar transmitter magnetron. Being a newly discovered phenomenon in 1945, Mr. Spencer was probably not aware that his own body parts were being likewise cooked, but he did recognize the commercial potential of an oven that used microwaves to cook food. It only took Raytheon (Amana) to have the first Radarange available for sale to professional kitchens. This article was printed a full decade after the discovery and even then the size and power consumption was too great for grandma's countertop. Of course grandma would never even...
Microwave and Millimeter-Wave Electronic Packaging, by Rick Sturdivant. Packaging of electronic components at microwave and millimeter-wave frequencies requires the same level of engineering effort for lower frequency electronics plus a set of additional activities which are unique due to the higher frequency of operation. Without careful attention to these additional issues, it is not possible to successfully engineer electronic packaging at these frequencies. This resource presents the packaging issues which are unique to microwave and millimeter-wave frequencies and reviews lower frequency packaging techniques and how they can be tailored or analyzed for higher frequency designs.
VidaRF introduces the VCI-120145-1, a 12.0 GHz to 14.5 GHz coaxial isolator which features a rugged body with stainless steel SMA connectors, sealed and painted if required. Isolation is 20 dB min, with an insertion loss of 0.4 dB or less, VSWR of 1.25:1, maximum power handling of 1W, and operational temperature of -54 to +85C. Other frequencies and connector configuration available per request in this package size of 0.50" x 0.67" x 0.50".
Website design has unarguably become a major source of headache for designers because of the widely varying non-standard standards for both desktop and mobile device displays. Compound that with the massive amount of information which needs to be fitted into the available space and the task is daunting. RF Cafe screen space has been necessarily (some say annoyingly) crammed with content. Some of the "clutter" has been necessitated by the need to make a living (i.e., advertising), but the majority is driven by a desire to provide as much data as possible without the need to endlessly scroll up and down pages and, most importantly, not having to click all around the website to find what you're looking for. One thing I implemented a long time ago was a unique (my original idea) menu system that avoids an HTML file...
In the days before space-based radio astronomy, observations on many frequencies required waiting until nightfall because the Earth's ionospheric activity interfered with signals in many bands of interest. Two such bands are 18 MHz and 20 MHz (16 and 15 meters, respectively), on which information on lightning-type discharges from Jupiter are received. Near-real-time maps of ionospheric absorption in the D layer (caused by solar x-ray activity) are available on the Solar Terrestrial Dispatch website for 5 through 30 MHz, which is where long-range high frequency (HF) communications occur. The F2 layer is where signals are usually reflected, but absorption in the lower D layer can be severe enough to limit reception.
"Do not blame Caesar, blame the people of Rome who have so enthusiastically acclaimed and adored him and rejoiced in their loss of freedom and danced in his path and gave him triumphal processions and laughed delightedly at his licentiousness and thought it very superior of him to acquire vast amounts of gold illicitly. Blame the people who hail him when he speaks in the Forum of the 'new, wonderful good society' which shall now be Rome's, interpreted to mean 'more money, more ease, more security, more living fatly at the expense of the industrious.' Julius was always an ambitious villain, but he is only one man." - Cicero, as quoted by the Honorable Millard F. Caldwell in Cicero's Prognosis
Electro-Photonics LLC is a global supplier of RF & Microwave components. Our products include SMT hybrid couplers, wire bondable passive components, coaxial products, test fixtures and very useful test boards for evaluating components. The Electro-Photonics team can support your small R&D design requirements with RF & Microwave test fixtures and save you valuable design and characterization time. Built-to-print and custom evaluation boards available.
This RF Engineering crossword puzzle is guaranteed to stump the most ardent weekly workers of the New York Times Sunday puzzle since its word selection is comprised entirely of the kinds of words and abbreviations that you and I are familiar with. Unless grandma was an engineer or scientist, it is doubtful she would know the answer to the clue, "Related to FM by a differential," but you probably do. Go ahead, give it your best shot.
Feedback has been widely misunderstood by many electronics enthusiasts, even those who have a fairly extensive background in circuit design (that which does not involve feedback). In fact, there have been instances of articles being printed in magazines like Popular Electronics, Radio-Electronics, etc., where the authors got relatively simple feedback equations wrong due to improper summing of nodes, necessitating a correction in a later issue based on reader feedback (a convenient and appropriate word for this comment). This article discusses feedback in audio circuits to avoid distortion, but the concepts apply to any frequency of operation. It is possible in many cases to implement seat-of-the-pants feedback schemes successfully...
The API725 Series is a high performance line of SAW oscillators providing superior communication distances for frequencies of 350 MHz to 4,000 MHz and phase lock loop for heritage applications. The radiation tolerant voltage controlled SAW oscillators (VCSO) are designed for space, satellite communications and aerospace systems. The VCSOs deliver low phase noise performance (-109 dBc/Hz at 1 kHz) and low vibration sensitivity (2 x 10-9 per g). API's space-qualified VCSOs are standard products that can be modified to customer
Being able to pass a 5 words-per-minute (wpm) Morse code test at one time was a primary requirement for obtaining the lowest level amateur radio operator license - Novice Class - in addition to passing a written test. Many more people failed the code test than failed the written test. In fact, the code portion kept many aspiring amateur radio operators from ever even taking the test. It was a barrier which anyone worthy of the brotherhood must overcome. The intimidation factor was pretty significant. As time marched on and the ranks of amateur license holders was dwindling quickly, the FCC in 1990 dropped the code requirement and created the Technician Class license that required only the passing...
Many people have contacted me over the years searching for the little "finger wrenches," aka "torque multipliers" and "thumb wrenches," that many display vendors have handed out for free at trade show booths. Like a lot of people, I have one of those plastic SMA tools as well with Agilent's name on it. Other people reportedly have versions with LeCroy's, National Instruments', Noise Com's, and other companies' names on them. My e-mails to at least three companies have never gotten responses. Another request just arrived, so I again searched the Internet using terms like "sma thumb wrench," "sma finger wrench," "trade show gift wrench," "sma plastic wrench," "plastic connector...
Witnesses suspect a rock from a snow blower might have hit the glass panel at Apple's 5th Avenue store. Maybe so, but if it were not for the Earth's rising temperatures, the extreme cold and massive snowstorm would never have happened and Apple's insurance company would not be looking at a $450,000 repair charge. It's yet another victim of anthropogenic global warming. Your 4WD pickup truck in effect broke the glass. A stander-by commented on the irony of the iStore's glass breaking like so many iPhone displays.
Thanks to the gracious contributions of Artech House, there are now four great new titles available for selection by winners of the monthly RF Cafe Book Drawing:
- Microwave and Millimeter-
Wave Electronic Packaging
- Bayesian Multiple Target
- Frequency-Agile Antennas
for Wireless Communications
- Reflectarray Antennas:
Analysis, Design, Fabrication
I use many of the books as the subjects of RF Cafe Quizzes and then make them available for selection in the drawings. Many times the selected winners never respond to my e-mail notifications, so after three e-mails I give up on them, making even more options available for the subsequent months' winner(s). Maybe you will be next!
The website is hosted in Greece by a Greek gentleman who contacted me about the "Subminiature Magnetic Amplifiers" article which I posted a couple days ago. Everything is published in English. He has a vast collection of technical data, much of which was self-published, and it is full of great photos from actual projects. You could spend hours clicking through the site looking at all the cool stuff. There is a section on magnetics with things like rope memory (used on the Apollo 11 moon shot), square loop toroids, and coincident current NOR gates, hand-drawn reverse engineering schematics...
IEEE JobSite Career Alert just sent out their latest list of good employment-related stories that you might find interesting. Well, the truth is I only post the ones I think you might find interesting. Visit their website to see everything.
- In Asia, Indian Workers
- Using Your iPhone for Work?
Bringing Your Own Device
Might Mean Losing Your
- Engineering Leadership
Lessons from Japan
- Discover Engineering Family
Day Scales New Heights
- The HR Capitalist: The 3
Ways Candidates Get
- 7 Reasons You Should
Update Your Resume Right
Now, Even If You're Not
Looking for a Job
- Jobs Open Up in Automobile
What do you buy the techie who has everything? How about a wristwatch that has a nixie tube display? I apologize for not discovering this little gem of Nerdom a couple months earlier to be in time for Christmas, but nearly everyone has a birthday, anniversary, graduation, or other special occasion between now and next Christmas for which the Old Nixie Watch can be presented. From the Cathode Corner website: "The Old Cathode Corner Nixie Watch is the perfect way to show your retro-geek cred. It is a two-digit wristwatch using Nixie tubes, a forty-year-old display technology that is delightfully easy to read. The watch requires no button-pushing to operate. Just hold the watch at your standard viewing angle, and the hours...
Anyone who has dealt with older electronics equipment knows that one of the first kinds of components to go bad is the electrolytic capacitor. Materials used at the time degraded fairly rapidly, especially compared to modern materials, which facilitated leakage of stored charge between the rolled up layers of conductive plates and interstitial insulating paper (or other material) layers. Symptoms of electrolytic capacitor malfunction in radio and television are most often some form of audible noise, light or dark lines within the picture scan, or outright power supply failure. Since electrolytics are typically large valued capacitors, they are used in power supply circuits for filtering the line 50 or 60 Hz (depending on your country) AC...
If you think your life in America is dictated by people you elect to office, think again. Unelected bureaucrats routinely write regulations that affect every aspect of your existence, including whether you will be considered for a particular job that you are technically qualified to perform, whether you are too 'privileged' to receive financial assistance for college, whether you can manufacture a particular type of light bulb, what kind of circuit breakers must be installed in your new home, how much of certain ingredients your food may contain, how many gallons your toilet may use...
In the middle of the last century, television technicians were considered nearly as god-like as doctors, especially those who made house calls to cure an ailing entity - be it a TV with its vertical synch circuit running amok or a child running a fever. OK, I exaggerate a bit, but General Electric mounted a media campaign to build a favorable image of TV repairmen in the public eye. People from every walk of life and of every type employment (well, maybe not mafia hit men and politicians), gave of their free time to help community efforts in charitable ways without any expectation of returned favors (which is why I included politicians along with mafia hit men). This 2-page advertisement which appeared in a 1958 edition of Radio-Electronics depicted TV technicians who were bestowed the "All American Award" for public service...
This article is provided as a reference to how these early vacuum tube transmitters were designed and built. Modifications in the circuit would be required to adapt this transmitter to modern standards. It is also a good reference for theory and operation of some of the older equipment that might be valuable for hobbyists who restore old radios - and there are a lot of us out here!
Energy Suckers: How to Deal With Bullies in the Workplace, by Barbara Bartlein. The work world is full of bullies who criticize, blame, intimidate, and humiliate others. In a study of U.S. workers, 41% reported experiencing psychological aggression at work in the last year. Bullying occurs in every industry and every profession. It is estimates that more than two million professionals and managers are pushed out of their jobs each year by bullying. This comes at a cost to employers of $64 billion a year. Decreased productivity, absenteeism, low morale and teamwork are all outcomes of a toxic work culture.
If you happen to be Estonian, you might think of something entirely different than most of us do when we hear the word "getter." In fact, you probably capitalize the word since it is the name of a pop singer from your country, Getter Jaani. If you are a child living in Japan, you would probably think of Getter Robo, an anime from a popular cartoon series. I, and I dare say just about everyone else that visits RF Cafe, knows getter as that silvery deposit (typically barium) that resides inside vacuum tubes for the purpose of helping to maintain the vacuum and to absorb pesky random molecules that might otherwise cause electrical noise in the circuit. This article from a 1958 edition of Radio-Electronics discusses the purpose of getter...
"It is inconceivable that inanimate Matter should, without the Mediation of something else, which is not material, operate upon, and affect other matter without mutual Contact…That Gravity should be innate, inherent and essential to Matter, so that one body may act upon another at a distance thro' a Vacuum, without the Mediation of any thing else, by and through which their Action and Force may be conveyed from one to another, is to me so great an Absurdity that I believe no Man who has in philosophical Matters a competent..." - Sir Isaac Newton, letter to Richard Bently, c. 1692
Robert Yarbrough, an independent consulting RF engineer, sent me information on a nice compact, inexpensive, wideband RF signal generator that he has developed. Joining what has become a very extensive array of USB-powered test instruments - signal generators, power meters, oscilloscopes, multimeters, spectrum analyzers, software defined radios, etc. - from various vendors, the TPI Synthesizer generates high spectral purity signals ranging from 35 MHz to 4.4 GHz with programmable output power levels from -55 to +10 dBm. Sweeping can be set for both frequency and power for testing both frequency and amplitude responses of passive and active devices. The unit can be locked...
Bittele is your complete Turn-Key PCB solution when it comes to Electronic Manufacturing Services. At Bittele we understand the requirements of, and specialize in, your companies' need for prototype and low-volume production. Our in-house facility provides PCB design & layout, design for manufacture (DFM), PCB fabrication, component procurement, and PCB assembly services. Because we do everything in-house at our ISO9001 certified and IPC-A-600 & IPC-A-610 compliant facility, we ensure your project is top quality and remains on schedule.
This was sent to me by an RF engineer friend of mine, who wrote it for his friend's wife whose husband is an RF engineer: "Ode to Old RF Guys: I'm sure you know, we old RF guys have bad joints (high power RF burned all the stuff between our bone joints away). A common malady is our ears don't work (too many loud booms from power amplifiers on the bench blowing up, too many straight out of school college kids telling us we don't know what we're doing, and managers yelling at us for schedule slips as physics is hard to trick). We have arthritis in our hands from too many times grabbing the needle nose pliers to tune coils, using tweezers to wrangle parts we can't see anymore, and the countless times we’ve tightened the RF connector at the end of a cable. We suffer from numb fingers from inadvertently touching too many over-temperature RF parts..."
2014 is shaping up to be a great year for magazine articles if these I have selected from Microwaves & RF and Test & Measurement World are any example.
- The Future of Connectivity:
Mobile & Automobiles,
by Jean-Jacques DeLisle
- Feedthrough in Negative-
by Sergio Franco
- Two-Wire Remote Sensor
Preamp, by Vlad Rentyuk
- Communications Continues
to Inspire Technology
Advances, by J-J DeLisle
SecureRF, a Connecticut based company, develops solutions that combine security and cryptography with low resource computing devices. Our breakthroughs in authentication and data protection performance are being applied to mobile payments, wireless sensors, machine-to-machine (M2M) and automated identification technologies such as NFC and RFID. As we bring our secure products to market and develop new security and sensor solutions, we are looking for RFID Hardware Engineers who have experience with RF wireless communication systems such as NFC and RFID to join our experienced team. More information and additional job openings can be found at the SecureRF website.
Here is this week's installment of my engineering, science, mathematics, chemistry, physics, astronomy, etc., based crossword puzzle. My custom dictionary of about 5,000 hand-picked words assures you that no idiotic clues for movie stars or clothing designers will get in the way. Enjoy!
Microwave Journal just posted a slew of good articles on their website. Here are a few of the ones I found most interesting, but you might find others that interest you.
- Next Generation Affordable
Smart Antennas, by
J.R. Guerci, T. Driscoll,
R. Hannigan, S. Ebadi,
C. Tegreene, D.E. Smith
- Generating Radar Signals
with an Arbitrary Waveform
Generator, by Chris Loberg
- Prototyping Massive MIMO
James Kimery, Ian Wong
- A Method to Design an
Using a MEMS Digital
Variable Capacitor, by
- A Very-Near-Field
Measurement Technique to
Test Large Antennas in the
Lab, by Ruska Patton
Established in November 1999, WOKEN is a Taiwan-based company that specializes in Microwave / RF coaxial connectors, cables, cable assemblies, Microwave / RF antennas and RF accessories. With the experienced R&D engineers & technicians, active marketing staff, up-to-date production equipment and measuring instruments, WOKEN designs its own RF / Microwave products for meeting all kinds of requirements demanded by its customers at communication markets.
Echo 1 launched in August of 1960, finally allowing America to participate in the Space Race, which until then was roundly being won by the USSR. Electronics magazines of the day were filled with prognostications of the future of space communications. Electronics World dedicated most of their November issue to satellite Earth stations and advancements being made in ultra sensitive receivers and powerful transmitters. Since the earliest satellites were literally metallic balls for reflecting radio signals, it was necessary to optimize both ends of the communications path since there were no circuits onboard the satellite to perform signal processing and re-transmission. Bell Labs, of course, was at the forefront of the technology. In fact a famously serendipitous discovery was made by a couple scientists in 1964 using the very antenna featured...
AWR Corporation, the innovation leader in high-frequency EDA software, will preview in Booth #1 new features and enhancements in its soon-to-be-released AWR Design Environment™ V11 at Radio Wireless Week 2014 in Newport Beach, CA from January 20 to 21. Of special interest are demos of the new configurable PCells (library of parts) antenna measurement capabilities in AWR’s Analyst™ 3D finite element method (FEM) EM simulation software.
Rohde & Schwarz has once again expanded the analysis bandwidth for its R&S FSW high-end signal and spectrum analyzers. In the past, 320 MHz was considered an excellent value. Rohde & Schwarz is the first company to offer analysis bandwidth of 500 MHz. The new R&S FSW-B500 hardware option is now available for all analyzers of the R&S FSW family and can therefore be used for measurements in a frequency range up to 67 GHz. This enables completely new applications for the signal and spectrum analyzer in research and development as well as for tests on fast wireless connections such as WLAN or Beyond 4G (5G).