Homepage Archive - April 2018 (page 2)

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Friday 20

Mac's Service Shop: Electronics and Psychology

Mac's Service Shop: Electronics and Psychology, May 1969 Electronics World - RF CafeJohn Frye, creator of fictitious electronics repair shop owner Mac McGregor and his sidekick technician, Barney, must have been an amateur student of brainology[sic]. This episode in a 1969 issue of Electronics World, and a recent story titled, "Biological Effects of Electrical Shock," which appeared in the May 1973 edition of Popular Electronics are proof of that. A very good introduction to the workings of nerve cells, axons, synapses, dendrites, etc., is given here. In a role reversal, Barney is educating Mac this time based on a psychology course he is taking at the community college. He goes beyond the "your brain is a ...

New Addition to RF Stencils for Visio: Panel Components

New Addition to RF Stencils for Visio: Panel Components - RF CafeBy popular request, a new set of shapes has been added to RF Stencils for Visio: Panel Components. These are built to the same scale as the test equipment and equipment racks in v3.0 so they will fit right in with your existing drawings. There are now more than 780 shapes in v3.1! Still only $35 (free to v3.0 owners) ...

QuinStar Next-Gen GaN Solid-State Power Amplifiers for Space

QuinStar Next-Gen Gallium Nitride Solid-State Power Amplifiers for Space - RF CafeSatellite communication is growing rapidly. Recent and anticipated launches of new satellite equipment are spurring interest in and demand for wireless communication. Several companies have stated the intent to provide large throughput, high-speed communication networks in the coming years. Along with the increased access to space, this is driving interest in new satellite communications. Accordingly, we need new communications technology to supply bandwidth and data rate to support these applications. One challenge ...

Could Holey Silicon Be the Holy Grail of Electronics?

Could Holey Silicon Be the Holy Grail of Electronics? - RF Cafe"Electronics miniaturization has put high-powered computing capability into the hands of ordinary people, but the ongoing downsizing of integrated circuits is challenging engineers to come up with new ways to thwart component overheating. Scientists at U. Cal., Irvine made a breakthrough recently in verifying a new material configuration to facilitate cooling. In a study in the journal Nanotechnology, members of UCI's Nano Thermal Energy Research Group highlight the attributes of holey silicon, a computer chip ..."

Thursday 19

Two-Wire Three-Way Switching Circuit

Two-Wire Three-Way Switching Circuit, July 1966 Popular Electronics - RF CafeI have to laugh a bit when seeing this article on how to wire up a set of 3-way switches "[i]f you only have a two-wire cable to work with." There have been many times when I needed to wire a set of 3-way switches and only had 2-wire Romex cable on-hand. The simple solution is to simply run two pieces of 2-wire cable and only use one wire from the second piece. A 250' roll of 14-3 w/ground costs about $79 at the hardware store. A 250' roll of 14-2 w/ground costs about $45. For short runs, the additional cost of using two pieces of 14-2 compared to a single piece of 14-3 is diddly. However, if you want ...

IMS2018 to Hold Student Design Competition

IMS2018 to Hold Student Design Competition - RF Cafe"The 2018 International Microwave Symposium (IMS), this year, will be held in Philadelphia from the 10 to 15 of June. This year one of the projects in the Student Design Competition is a 16-quadrature amplitude modulation (QAM) radio. The competition will be based on a course offered by Dr. David S. Ricketts from North Carolina State University. The competition leverages Dr. Ricketts' hands-on workshop, known as 'From Bits to Waves: Building a Modern Radio in One Day,' which successfully combines the use of NI AWR Design Environment with design labs to ..."

NI AWR Software Featured in Balun Design Webinar

NI AWR Software Featured in Balun Design Webinar  - RF CafeApril 26, 2018, 11 am ET. NI AWR Design Environment will be featured in a webinar on designing a printed balun for a wide bandwidth L-band 200 W power amplifier (PA). The design begins with an idealized circuit simulation in Microwave Office circuit design software using closed-form transmission line models, followed by a more rigorous EM simulation conducted using AXIEM 3D planar EM solver. The webinar is presented by Dr. Dominic FitzPatrick of PoweRFul Microwave, who ...

Designing with Plastics for Military Equipment

Designing With Plastics for Military Equipment - RF CafeThe April issue of Aerospace Defense magazine has an interesting article titled, "Designing with Plastics for Military Equipment," that discusses how plastics are replacing metal parts in military equipment. Included is a useful table of plastic types, their properties, and examples of their applications ...

Wednesday 18

The Antenna Specialists Co. Advertisement

The Antenna Specialists Co. Ad, July 1966 Popular Electronics - RF CafeHere's a gimmick that never really caught on. In the 1960's, Antenna Specialists promoted their Model M−148 Co-Ax Omni Antenna "with visual RF indicator." That indicator was a neon light bulb at the tip which lit up when the transmitter was keyed on. Not only would this novel feature let you know when your transmitter was broadcasting, but it would also "guide mobiles visually to your 10-20." OK, maybe at night, but it certainly wouldn't have been bright enough during the day to even see. Alas, the public evidently didn't impress the buying public as much as it did the designers. Maybe it had something to do with ...

Transient Specialists' AVI3000 Avionics EMC Immunity Test System

Transient Specialists' AVI3000 Avionics EMC Immunity Test System - RF CafeTransient Specialists, a leader in electromagnetic compatibility rentals for over 40 years, announces that they will be offering a discount price on the AVI 3000 for the month of May. This all-in-one 6 waveform portable test unit allows easy on-site testing to full level 3 threat under all load conditions. This product is ideal for testing to DO 160 Sec. 22 Level 3 and Mil Std. 461 CS 117 Waveforms 1, 2, 3, 4, 5A, and 6. Transient Specialists, conveniently located in the mid-west, offers a variety of EMC test equipment rentals to accommodate your testing needs ...

Electronics-Themed Comics, July 1969 Electronics World

Electronics-Themed Comics, July 1969 Electronics World - RF CafeHere are a couple more electronics-themed comics from a 1969 edition of Electronics World magazine. I like the radio astronomy comic. Enjoy ...

Gunn Oscillators: A Reintroduction

Gunn Oscillators: A Reintroduction - RF CafeYonghui Shu, president of SAGE Millimeter, offers a primer on Gunn diodes used as mm-wave oscillators. It appears on the HFE website. "The semiconductor used in the Gunn oscillator is called the 'Gunn diode.' The Gunn diode is a two-terminal 'negative' resistance device. The Gunn diode is also referred to as a 'Transferred Electron Device' which was invented by J. B. Gunn in 1963. Since their invention, Gunn oscillators have been playing a unique role in replacing the tube to generate low to medium level ...

Many Thanks to ERZIA for Continued Support!

Many Thanks to ERZIA for Continued Support!RF Cafe's continued existence depends on companies like ERZIA providing support. ERZIA produces microwave and mm-wave modular amplifiers and integrated assemblies operating from Low frequencies up to 100 GHz. Their catalogue of standard amplifier modules comprises more than 100 different models, having also a high capacity of customization for amplifiers and integrated assemblies. Some of products have space heritage and are used in aerospace, commercial, military and scientific systems, having a wide range of final applications ...

Radio Over Fiber Paves Way for Future 5G Networks

Radio Over Fiber Paves Way for Future 5G Networks - RF Cafe"A manufacturer of III-V photonic devices claims to have proven the feasibility of 60-GHz radio over fiber (ROF) transmission at a 1,270-nm wavelength, paving the way to potential solutions for 5G networks. CST Global, a Scotland-based subsidiary of Sivers IMA Holdings AB in Kista, Sweden, carried out the feasibility study as part of an EU Horizon 2020 research project. The company says that ROF networks are emerging as a completely new and promising communication paradigm for delivering broadband wireless access services and ..."

Tuesday 17

Generating Multiple Phase Coherent Signals

Generating Multiple Phase Coherent Signals - RF CafeTesting multi-antenna systems such as phased array or beamforming antennas requires a test system capable of providing multiple signals with constant phase relationships between them. The coherent test signals must have a specific or definable phase difference (relative phase) and definable amplitude. Some of the challenges for such a test system include compactness, phase control capability and simplicity in handling. In particular, phase stability between the channels is of importance. This application note ...

The Future of Automotive Radar Testing

The Future of Automotive Radar Testing - RF CafeMr. Matt Spexarth, of National Instruments, offers his insight into the future of automotive radar testing in his Microwave Journal article. "Radar has multiple advantages over alternative sensing technologies, securing its role in automotive active safety and autonomous driving well into the future. Radar has the unique abilities to instantaneously detect the velocity of detected objects via the Doppler shift of their radar signatures, and to penetrate inclement weather conditions such as rain, fog and snow. These benefits are driving automakers ..."

Are There Too Many Short-Range Wireless Standards?

Are There Too Many Short-Range Wireless Standards? - RF CafeLou Frenzel has another good article over at the Microwaves & RF website. Sez Mr. Frenzel, "Do you know how many wireless standards there are? More than you think. Just recently I made a list of all the short-range wireless standards I could think of - more than 30 in total. I did not include any proprietary designs that fit things like garage door openers, remote keyless entry on vehicles, weather stations, tire pressure monitoring, or all those other unique ISM band wireless devices. That got me to thinking about how an engineer chooses a standard ..."

How to Stack TV Antennas to Increase Signal Strength and to Reduce Ghosts

How to Stack TV Antennas to Increase Signal Strength and to Reduce Ghosts, November 1965 Popular Electronics - RF CafeYou probably won't find too many people stacking television antennas these days, but many Hams still do it. Vertical stacking is used primarily to increase overall gain without appreciably altering the azimuth beam, while horizontal stacking forms a tighter azimuth beam without appreciably affecting the overall gain. When it comes to optimizing antenna designs installations for operations below about a gigahertz, Amateur Radio practitioners have pretty much written the book on the subject - actually, they have written hundreds of books on the subject. Antenna stacking is often used ...

Thanks to Anatech Electronics for Long-Time Support

Anatech Electronics logo - RF CafeAnatech Electronics (AEI) manufactures and supplies RF and microwave filters for military and commercial communication systems, providing standard and custom RF filters, and RF products. Standard RF filter and cable assembly products are Anatech Electronics RF Filterspublished in our website database for ease of procurement. Custom RF filters designs are used when a standard cannot be found, or the requirements dictate a custom approach. Please visit Anatech today to see how they can help your project succeed!

What About the In-House Innovators?

What About the In-house Innovators? - RF Cafe"Silicon Valley has become a must-visit destination for Department of Defense leaders in recent years. But the push for more public-private partnerships could have an unintended side effect - overlooking government's longstanding research and development resources. Arun Seraphin, a professional staff member for the U.S. Senate Committee on Armed Services, said he thinks the fixation on startup-culture innovation has gone too far. 'We like to say that every time a senior leader flies to Silicon ..."

Monday 16

The FCC's Big Problem with Small Satellites

The FCC's Big Problem with Small Satellites - RF Cafe"Confusion and erratic enforcement at the US communications agency is sending satellite makers abroad. When officials at the Federal Communications Commission (FCC) denied launch authorization for four innovative satellites from startup Swarm Technologies last December, the agency was unequivocal as to the reason. 'The applicant proposes to deploy and operate four spacecraft that are smaller than 10 centimeters in one of their three dimensions,' read a letter to Swarm's CEO and founder Sara Spangelo. 'These spacecraft are ..."

Pasternack Coaxial RF Probes and Probe Positioning Hardware

Pasternack Unveils Innovative Line of Coaxial RF Probes and Probe Positioning Hardware - RF CafePasternack, a leading provider of RF, microwave and millimeter wave products, has just launched a new, innovative line of coaxial RF probes and probe positioning hardware. These new products are well-suited for signal integrity verification, chip evaluations, coplanar waveguide, circuit debugging and test fixture applications. Pasternack's new product line consists of four coaxial RF probes and one RF PCB probe positioner with unique designs. The RF coaxial probes deliver frequency performance up to 20 GHz and return loss better than 10 dB ...

Burgess Salutes United on 20th Anniversary of Transcontinental Airmail

Burgess Salutes United on 20th Anniversary of Transcontinental Airmail, January 1941 QST - RF CafeThis thankful commemoration of the 20th anniversary of U.S. Air Mail service from Burgess Battery Company, which appeared in a 1941 issue of QST magazine, encompasses most of my major lifetime interests. First and foremost, from my earliest memories, is a love of airplanes (and all things that fly for that matter). A DC−3 (my favorite multi-engine propeller plane) is shown in one of the photos as is a Ford Trimotor, which Melanie and I have flown on. Next comes the electrical, electronics, and radio communications aspects, which encompasses the aircraft wiring ...

Solving RF Isolation Issues with RF Inductors

Solving RF Isolation Issues with RF Inductors - RF CafeCoilcraft is offering a free app note titled "Inductors as RF Chokes." "Many consumer products communicate with each other over broadband networks. From television to fiber trans- mission networks, the bandwidth of data communication is increasing, and the integrity of RF signals has become a major design concern. This paper provides examples of how different inductors can be used for RF isolation in a range of circuits from relatively narrow band applications like portable devices up to broadband networks for data distribution. The different types of inductors ..."

Metal-Printed Waveguide Filter

Air-Worthy Metal-Printed RF Filter - RF Cafe"Within the aerospace industry, 2016 and onwards could be looked upon as the tipping point for direct metal printing (DMP), as the technology increasingly made the jump beyond prototyping to production parts and assemblies ready for flight. During that time frame, Airbus Defense and Space worked with 3D Systems (Rock Hill, SC) to achieve a major breakthrough: The first 3D-printed radio frequency (RF) filter tested and validated for use in commercial telecoms satellites. The project built upon research funded by the European Space Agency ..."

Sunday 15

RF Cafe Engineering & Science Crossword Puzzle April 15

RF Cafe Engineering & Science Crossword Puzzle April 15, 2018Each week, for the sake of all avid cruciverbalists amongst us, I create a new technology-themed crossword puzzle using only words from my custom-created lexicon related to engineering, science, mathematics, chemistry, physics, astronomy, etc. You will never find among the words names of politicians, mountain ranges, exotic foods or plants, movie stars, or anything of the sort. You might, however, see someone or something in the exclusion list who or that is directly related to this puzzle's theme, such as Hedy Lamar or the Bikini Atoll, respectively ...

Friday 13

Cup Cylindrical Waveguide Antenna

Cup Cylindrical Waveguide Antenna - RF Cafe"NASA Glenn's cup cylindrical waveguide antenna (CCWA) is a short backfire microwave antenna capable of simultaneously supporting the transmission or reception of two distinct signals having opposite circular polarizations. Short backfire antennas are widely used in mobile satellite communications, tracking, telemetry, and wireless local area networks because of their compactness and excellent radiation characteristics. Achieving simultaneous dual-circular ..."

Please Welcome Rohde & Schwarz USA as a Supporter !

Rohde & Schwarz RF Component Pocket Guide - RF CafeRohde & Schwarz (R&S) is promoting the availability of their free RF Component Pocket Guide. I posted an article about it and some of their posters and pocket guides. R&S develops, produces and markets test & measurement, information and communications technology. It focuses on test and measurement, broadcast and media, cybersecurity, secure communications and monitoring and network testing, areas that address many different industry and government-sector market segments. Specifically: test and measurement for the wireless market, automotive industry ...

Solid State - Early Mention of GaAs

Solid State - Early Mention of GaAs, April 1966 Popular Electronics - RF CafeWhen is the last time you heard someone refer to electronics as "solid state?" It was a necessary differentiator during the era of transition from vacuum tubes to semiconductors. Mere utterance caused fear in some, and futuristic hope in others. "Solid State" was a big buzz phrase in marketing to household consumers and industry planners. Why, I ask, was "solid state" chosen as the term to counter vacuum tube electronics? Did we ever refer to tubes as "gaseous state" or "plasma state" devices? Maybe the "solid" part of "solid state" evoked a sympathetic emotion with the coincident hippie / beatnik era population's usage ...

Electronic Component Sculptures

Electronic Component Sculptures - RF CafeWhile doing a little research about a Popular Electronics article, I ran across some examples of electronic component art / sculpture. A Google image search on the topic yields hundreds of results, with most being duplicates. I always try to locate the original image so as to give proper credit to the designer, but more often that not the pictures are posted on websites without a reference. To avoid unfairly attracting attention from the creator's work, I always use thumbnails and provide hyperlinks to the websites where I found ...

International Conference on Microwaves for Intelligent Mobility

International Conference on Microwaves for Intelligent Mobility (ICMIM2018) - RF CafeThe fourth annual IEEE MTT-S 2018 International Conference on Microwaves for Intelligent Mobility (ICMIM 2018) will be held on 16-18 April, 2018 in Munich, Germany. This conference covers a broad range of topics that enable intelligent mobile systems through RF / microwave / mm-wave components, circuits and systems. Potential applications include cognitive and autonomous automobiles and robots, wireless communications between automobiles and industrial machines. ICMIM2018 is sponsored by the IEEE MTTS and technically ...

Sound Inaudible to Humans Can Be Recorded by Microphones

Sound Inaudible to Humans Can Be Recorded by Microphones - RF Cafe"An inaudible signal that translates to white noise in the microphone can prevent unauthorized persons from recording voices. Researchers have designed a sound that is completely inaudible to humans (40 kHz or above), yet is audible to any microphone. The sound combines multiple tones that, when interacting with the microphone's mechanics, create what researchers call a 'shadow' - a sound that the microphones can detect ..."

Thursday 12

Why Noise Can Enhance Sensitivity to Weak Signals

Why Noise Can Enhance Sensitivity to Weak Signals - RF Cafe"Researchers have discovered a new mechanism to explain stochastic resonance, in which sensitivity to weak signals is enhanced by noise. The finding is expected to help electronic devices become smaller and more energy efficient. Noise is generally a nuisance that drowns out small signals. For example, it can prevent you from catching what your partner is saying during a conversation. However, it is known that living organisms find it easier to detect predators in noisy environments since noise enhances the sensitivity of the sensory ..."

Windfreak Technologies Intros SynthNV PRO at WAMICON 2018

Windfreak Technologies Intros SynthNV PRO at WAMICON 2018 - RF CafeWindfreak Technologies attended WAMICON 2018 in Sand Key, FL, as an exhibitor in the vendors hall. Windfreak demonstrated its new product the SynthNV PRO which is the next generation of the popular SynthNV. Windfreak Technologies has shipped thousands of the original SynthNV around the world since its release in 2010. The SynthNV PRO is a highly calibrated 51 MHz to 6.6 GHz RF Signal Generator plus 8 GHz broadband RF detector / power meter. The SynthNV accomplishes Scalar Network Analysis for both through and reflected responses ...

Capacitor Know-How Simplifies Electronic Projects

Capacitor Know-How Simplifies Electronic Projects, July 1966 Popular Electronics - RF CafeFiltering, timing, coupling, and energy storage are the most common uses for capacitors (not to mention their use in electronic component sculptures). Metallized paper or plastic, plastic film, mica, ceramic, electrolytic, and a few other capacitor types have been around for a long time, with newer formulations of electrolytics providing higher charge storage density, lower leakage, greater stability, lower cost, wider operational temperature ranges, more robust construction, etc. We now have supercapacitors that ...

New Dielectric Constant Data Added

Dielectric loss tangent - RF CafeThanks to RF Cafe visitor Alois B. for providing additional resources for the material dielectric constants page. Now included are Electrical Properties of Insulators and Dielectric Properties of Materials.

Saelig Intros LeCroy WaveSurfer 3000z, 4−Ch, 1 GHz O−scope

Saelig Intros Teledyne LeCroy WaveSurfer 3000z, 4-Channel, 1 GHz Oscilloscope - RF CafeSaelig Company announces the availability of the Teledyne LeCroy WaveSurfer 3000z 4−channel Oscilloscope range, offering 100 MHz - 1 GHz bandwidth, capacitive touch capabilities, huge memory, and a comprehensive tool box - all at a remarkably affordable price in a compact, small footprint product. Featuring the industry's most advanced user-interface - MAUI - on a 10.1" capacitive touch screen, the scopes all have 20 Mpts of memory, multi-instrument capabilities, a selection of powerful internal test tools and a sample rate of up to ...

U.S. Broadcasters Using Antennas Based on Variable Polarization

U.S. Broadcasters Have Started Using Antennas Based on Variable Polarization - RF Cafe"Radio Frequency Systems (RFS) is helping major U.S. broadcasters future-proof their systems against the Spectrum Repacking announced by the FCC. The FCC released a public notice announcing that they will repack the television band by assigning television stations to new channels. Nearly 1,000 stations will be moved to new channels starting November 2018. RFS is using its patented Variable Polarization Technology (VPT), to address global deployments and US-specific demand. They have now installed ..."

Wednesday 11

Anatech Electronics' April 2018 Newsletter

Anatech Electronics Newsletter for April 2018 - RF Cafe

Anatech Electronics, a manufacturer of RF and microwave filters, has published its April newsletter. In it, Sam Benzacar digresses from his usual insight into military and commercial telecommunications topics to address the potential for election fraud. It is not a politically charged treatise, but a commentary on the vulnerability of cybersecurity efforts - basically concluding that other than with old fashion paper ballots, meddlers have ample opportunity to rig the system without ever physically showing up at polling sites. Of course we ...

Fundamentals of Solid-State Receivers

Fundamentals of Solid-State Receivers, February 1972 Popular Electronics - RF CafeRF, IF and baseband amplifiers; RF, IF, and baseband filters; fixed and tunable local oscillators, single- and double-balanced mixers, attenuators, envelope detectors and phase detectors, directional couplers, power combiners and dividers, et cetera, are all component types used for receiver systems regardless of whether vacuum tubes or transistors comprise the active parts. In 1972 when this article appeared in Popular Electronics magazine, people were beginning to get comfortable with the idea of transistorized products replacing the familiar tube. Instant-on televisions and radios were ...

High-Resolution Measurements with R&S Oscilloscopes

High-Resolution Measurements with R&S Oscilloscopes - RF CafeRohde & Schwarz has published a new app note titled, "High-Resolution Measurements with R&S Oscilloscopes." It is available as a free download. "The introduction of high-resolution oscilloscopes is the response to the increased necessity for more in-depth signal analysis in particular in A&D, automotive, medical and power analysis applications where it is often required to view signals with both large and small voltage details. Characterizing Switched Mode Power Supplies (SMPS) is one example. To perform accurate power measurements the oscilloscope must acquire the ..."

Nano Drumheads Receive and Transmit Wide Range of RF Signals

Nano Drumheads Receive and Transmit Wide Range of RF Signals - RF Cafe"Making the next generation of ultralow-power communications and sensory devices smaller and with greater detection and tuning ranges, researchers at Case Western Reserve University are developing atomically thin 'drumheads' able to receive and transmit signals across a radio frequency range far greater than what we can hear with the human ear. The drumhead is tens of trillions times smaller in volume and 100,000 times thinner than the human eardrum. Sensing and communication are key to ..."

Soaring 'SuperTowers' Aim to Bring Mobile Broadband to Rural Areas

Soaring 'SuperTowers' Aim to Bring Mobile Broadband to Rural Areas - RF Cafe"One tethered, autonomous aerostat [aka 'blimp'] flying at 250 meters can provide as much coverage as 20 or 30 cell towers. It's 2018 and more than 16 million people living in the rural United States still lack adequate access to mobile broadband. But building out that infrastructure is an expensive endeavor. One analysis from 2017 estimates it would take 37,500 new cell phone towers and run upwards of $12.5 billion to bring 4G to rural areas in the United States, including Alaska, Hawaii, and Puerto Rico ..."